When the game comes out, and we get a look at those sweet, sweet character creation rules, who do you intend to make and play as? Assuming your group doesn't insist you GM, that is.
Personally I'm thinking about making Good!Proletariat (aka Everyman), because I've always loved that powerset, and I'd enjoy the shenanigans of being able to deal with an environment obstacle and a villain or two, all at the same time.
I've got a couple of ideas. I think that the one I like the most is Flashbang - a teleporter who, rather than quietly popping in and out all over the place like most teleporters, displaces the air in the area they are filling - pushing it outwards at high speeds creating a sonic boom. (When they teleport away, of course, it produces a vacuum which then rapidly fills.)
No real thoughts about personality/history yet.
The power was inspired by the Young Wizards series, where teleporting causes this exact sort of effect unless air displacement is included as a variable in the spell.
I have a bad habit of recreating the same character multiple times, especially when I feel they haven't had a chance to properly shine yet.
So, the character I've been rewriting is a magic-using hero with a "dark" spirit attached to him. The spirit is "The Beast with the Broken Name" and it and my character have reached an understanding and compromise. Part of that compromise is the hero name, Damocles was the best commmon ground they could find.
Power set is magic, but magic more similiar to Harry Dresden in that the majority of his power, in my mind at this time, comes from pre-enchanting items and planning ahead with various items. Writing is going to be an important part of that, I like the idea of the Beast being from the time of Ancient Sumer, when Writing was created and considered pure magic.
I spend a lot of time thinking about characters for various games instead of doing other things I should probably be doing.
The GM
What? You asked... 
Oh man, the Young Wizards series were my favourite when I was young! I love Flashbang as a concept, I think he'd be heaps of fun. It's interesting, C+A commented on the Letters Page that they don't have a teleporter because that power doesn't do much necessarily in the card game form, but I can certainly see it working in the RPG.
Damocles sounds excellent - I really like the Dresden Files, to start with, and I also get a bit of an Etrigan vibe with the uneasy alliance with The Beast. I'd love to see how that shakes out!
I'd really like to go with my "random powers" concept, it's just a question of, is there at least a basic list of powers from which a random roll can produce a result?
That could be highly entertaining, but would be challenging to roleplay. I really like that idea! It would take the right kind of personality to pull it off, but it could be impressive if done well. 
I'll likely end up GMing this game and only rarely playing, but...I'd like to expand upon the sorcerous lore in Sentinels, perhaps through some sort of arcane character, possibly linked with Zhu Long. Lots of bargaining with unsavory forces, in an attempt to stave off the evils of the moment. One part John Constantine, one part Etrigan, and one part Ghost Rider.
I see this character as channelling various demons, each providing different advantages/drawbacks, as his soul is slowly whittled away...
If I get a chance to actually play, which I wont, because life and stuff, I would make a super powered by her ownership of excalibur. I am unoriginal and love those public domain tropes
I always wait to see what setting the GM has in mind and who the other players would like to play so that my character will fit in well with the team and story. Typically I'll read a rulebook and immediately have a whole bunch of ideas for characters I'd like to design--I was recently invited to join a Star Wars Saga campaign, and by the time I was done reading the core rulebook, I had a list of 4 different characters to choose from. (Unfortunately the game never got started, so all 4 ideas, including the full character sheet for the one I went with, are collecting dust.)
On advantage of the base setting assumptions of the game is that making a character who "fits in" with the team is a very low bar to set.
Just look at the Prime Wardens
An Ancient Immortal Warrior
A Alien Refugee
A Magical Musician
God's Avenging Angel
A Space Cop
They share almost nothing and it's almost random how they fit together. Your team in the canon assumption is a bunch of fledgling heroes seeking training and respectability from the major team (Sentinels of Freedom) and that really opens up the "who can we smash together".
Compared to other games where team compisition can be a major concern for the group at session zero
Well in D&D I was already "that one player who always wants to play the bard", so... yeah. :3
But I'm with MindWanderer, I'm also open to whatever the GM wants to tell. It's too easy to end up with characters who have personal goals and traits that fit with each other or the GM's intended plot not at all.
Chaosmancer: Honesly one of the questions I'm going to ask in the Prime Wardens episode is "what are their interpersonal dynamics even like" because there's so many contrasting cultures and personalities in that group.
I wasn't thinking about story, that can usually be handled in one way or another unless you come up with a character who is completely antisocial or who has one driving goal that shuts out all others. I was thinking more in terms of team composition. The Prime Wardens have a tank/bruiser, a cleric/paladin, a mage/leader, a blaster, and a support/utility. It's almost the classic D&D 5-person team. Same with the Freedom Five: leader/protector, bruiser, skill/striker, skirmisher/controller, and blaster. Dark Watch, not so much, but then, I've always thought they were the least functional and cohesive team of the three.
So as a thought experiment and example: what character would I choose if I were joining Dark Watch pre-OblivAeon (since I don't know what Harpy can do, really)? They have Setback (tank/bruiser), Mister Fixer (bruiser), Expatriette (striker), and Nightmist (controller/blaster). Their biggest lack is someone with healing and protection abilities–Nightmist can heal herself only, and Setback protects others only by drawing damage to himself. They certainly don't need any more direct damage! So I'd probably come up with someone functionally similar to Argent Adept to join them–someone who can heal Setback, augment damage and defense, and deal with unusual situations that arise.
That is a cool thought experiment, but I must say, our biases towards D&D thinking come in strong.
Looking at Dark Watch and wondering what they lack as the protectors of a city, I'd bring in someone who can infiltrate a group, spy, and talk to people, build connections.
Expat and Dark Watch Fixer are very much not good with people. All of them stand out like a sore thumb, especially Setback. And Nightmist is no longer human, so who knows what shenagins she deals with. She also seems too preoccupied for that sort of work. Setback is the most charismatic, yet his dorkiness and penchant for looking the fool might end up hurting him for long term work. And yet, they would need to ferret out the Cult after it has been forced even deeper into the Shadows and the Remnants of the Organization that has slunk away to lick its wounds and it is probably being ran much more sneakily since the Chairman now has to consider a full time team in the city, with more public support than ever before.
My first thought was an investigator, but Nightmist solidly hits that checkbox and Expat is a good secondary.
I'm not sure how this game is going to run long term, but I do wonder how much of a combat game it will be compared to a game about investigations and just storytelling.
I think I'll already have to add in some optional rules for scenes where people roll against a lower difficulty. Scenes like Legacy digging a trench in a poor village or Unity creating a swarm of bots to clear away some rubble. The stuff that isn't urgent but helps build the narrative as connective tissue before or after a session, but not the montages where you heal and prepare… I don't know, the strucuture of the actual sessions is something I'll have to get a solid feel for since I don't know if I like side-scrolling to the next fight over and over again.
In the event I have time to play and am not running, I'm so totally take a re-do of Lacuna. I've got a better grip on some parts of her personality and issues she's going to be dealing with along the way assuming the GM is open to it (addiction - not as substance abuse, but to using her powers).
I relate SO much.
Anyway, mine will be a teenaged Virtuoso (You mean there's music other than pop or emo?) , who often finds his regular life and the world of superheroing overlapping. Trying to figure out his instrument. Any ideas (shameless crowdsourcing)?
I kind of like the idea of a folk music Virtuoso who is excited about the idea of getting to adventure around since it means they can learn different cultures' stories from their folk and religious music.
There's nothing that says the instruments have to be unique. HOwever, if you want to follow Jeysie's idea of a folk-based one, then drums or a simple stringed instrument are the easy options.
WE NEED A VIRTUOSO WITH A HURDY-GURDY
Ahem. Sorry for shouting, I just think it's a cool idea. :D
Don't make me dig up the thread we had with everyone coming up with weird ideas for Virtuoso instruments. ;P
(I'm still amused that I joked that we needed a Virtuoso who plays the recorder because everyone gets stuck playing it in middle school, and then we find out Anthony decided to play the pipes because he remembered playing the recorder in middle school.)