We only know the one new ability for a single class so it's far too early for most to judge. Me, I'll be going with Vanguard since it's the class my very first Shepard has been since the beginning, and I wanna keep him consistent 8)

yeah, ill be going vanguard probably as well. i was a vanguard in ME1 and ME2 (tried other classes, none seemed as cool). i mean biotic stuff and being good with guns? hell yeah.

Soldier. I like bringing the big guns. Though now when all classes can pick weapons of choice, while using fewer slots, I wonder if the soldier will get anything in particular to make it more interesting. Being able to carry all weapon types at once feels like a rather weak benefit, since you often choose a couple of favorite weapons and stick to them anyway.

That new melee focused one sounds fun.

Adept 
 
Same as ever. 

Vanguard, for consistency with my lead Shepard. I might try an adept on one of my other characters. I wasn't a huge fan of how the Infiltrator played in ME2. I really wanted to like it, but couldn't. I might consider it if there are some new modifications, but I think the changes to classes this time around will probably be pretty small. Maybe they'll surprise me, who knows.

Adept like I did for ME1 and ME2. Although I did play as the Soldier on my first play through of ME1 it was really boring running into every room and hosing it down with bullets. 

Adept for femshep and vangaurd for my dude

original gangster 

Soldier, then infiltrator/vanguard next. I like the better weapons the soldier has.

Vanguard

I'll definitely be sticking with the Vanguard bandwagon. Granted, it's the class I've stuck with since ME1 continued through ME2. 
 
I look forward to being able to biotically punch people into space.

Vanguard or Adept. I need my biotics. 

Vanguard, as I was in ME1 and 2.

I always pick Vanguard, then I played Soldier on my Insanity run for ME2.

I've been an Infiltrator for 1 and 2, not gonna change it for 3.

Same as the one I chose in Mass Effect and Mass Effect 2. Soldier to the end.

My first playthrough is always as a Sentinel.

Vanguard first playthrough, soldier second and will probably play the second playthrough by saying all the lines through my Kinect

Never be not sniping.

I like playing either Infiltrator or Sentinel.

Vanguard 4 lyfe.

Soldier, but sometimes I'll play as an Adept, but mostly soldier. 

Adept.

soldier for sure (because that was one of my characters from 2 and i probably was going to anyway) and then my other character from 2 idk what who im going to play

@akiz_jack said:

Same as the one I chose in Mass Effect and Mass Effect 2. Soldier to the end.

Same here.

Infiltrator all the way.

Infiltrator and soldier, not sure which I'll play first though and which of my Shepards I'll import first.

I GO THAT MANGO SENTINAL!

Only ever played as vanguard so ill keep it up i guess.

I shall enter the void just as I did before... as a soldier.

The ones I import from the previous games?

Vanguard 4 life dawg

Probably soldier first time through, but I'll wait to see what other info we get on the other classes. Vanguard was really fun so I might go with that.

Im going to use Soldier, Inflitraitor and Vanguard. Maybe i will use all of them who knows, but Mass Effect is always awesome and cool sci-fi story.

Sticking with Vanguard. I have been one since the very beginning.
 
I just love charging into dudes and shotgunning them in the face.

If they're revamping the classes again, I might choose an entirely different class. Though the easiest one for me typically is Soldier. I usually do a playthrough with about 4 classes anyway so it doesn't make a huge difference to me.

Infiltrator, cannot wait to use the Widow again. And the widow was in one of those E3 videos being used by some blue armored alliance guy.

My first play through will be as an infiltrator, which is the class of the character I will be importing.   Eventually, I will play with most, if not all of them.  I have about 6 characters ready to be imported...all of them will be imported at some point.

@akiz_jack said:

Same as the one I chose in Mass Effect and Mass Effect 2. Soldier to the end.

this... the other classes sound cool, I remember my first play through on mass effect wondering when I would unlock the cool biotic stuff, then I realized that was never going to happen due to my choice at the beginning of the game. Then ME2 came and after reading all of the descriptions. Soldier was still the most sound and tactical choice.

Infiltrator, Sentinel, Vanguard, Adept, Soldier, and Engineer in that order.

Adept for my "real" shepard, soldier for my asshole shepard yet again. 

Soldier, my shepard has been Soldier for two games now so it'd be good to keep it the same. For another playthrough I'd try a different class but not enough details have been given that I'd know which one in ME3.

My main is a Soldier, then an adept, then an infiltrator I believe.

Infiltrator for my female Shepard (which is the REAL Shepard as far as I am concerned), for my male one I'll look and see how the classes develop.

Soldier.

soldier all the way

in my universe shepard is a soldier

Infiltrator