Microsoft-$$ solves all the problems!

Sony-I wish we had $$ to solve our problems.

Nintendo-We're losing $$! Quick! MOAR MARIO.

EA Sports: "It's in the game but we're still gonna make you pay extra for it."
Capcom: "Driven to screw over early adopters again and again"

NIntendo. "Get N or go F yourself."

Sony for PS3 "It only does everything... until we remove another feature."

Microsoft for 360. "We'll replace your console free for up to three years."

I laughed out loud at this :)

Here are mine. I decided to play it serious.

Microsoft: Live the room
Nintendo: Together we play (stylized as Together Wii Play)
Sony: One for all (stylized as One 4 All)

Sony: "Our games might not sell, but they sure are great!"
Nintendo: "Here kiddy kiddy kiddy"
Microsoft: "You buy it, we break it"

Sony: "3rd parties help us! ...No, you're not getting any money."
Microsoft: "Say you like Kinect...SAY IT."
Nintendo: "Hahaha! It prints money!"
EA: "Fuck you...now please buy our games."
Square Enix: "Please be excited."
Capcom: "Super X 2.0 Director's Cut edition, now with 2 more characters."

This thread is going pretty well, no trolling and some pretty funny slogans.

That's a great one for Sony, litterally laughed out loud.
I didn't know you had it in you :)

Ok, here we go:
SONY: We will die trying to please you.
MICROSOFT: We will profit from Sony´s death, also we will not try to please anyone.
NINTENDO: We don´t need a slogan, we got Mario.
RARE: We are nothing but a shadow of what we used to be. (catchy!)
SQUARESOFT: Alive till you forget that once Final Fantasy was awesome.
ACTVISION: We don´t need a slogan, or a new engine, we got Call of Duty.
E.A.: We will change the game you loved till it sucks, except Fifa, in Fifa we will not change a thing.
UBISOFT: We got 11 Assassins Creed for each Rocksmith

Might as well do the big 3:

Nintendo: "Wii want U to buy our new console... we mean it... PLEASE BUY IT!"
Sony: "We sell consoles... and buildings! Oh and portables too, from time to time."
Microsoft: "We still believe motion control is a thing"

Bonus:

SquareEnix: "Remember when we used to be great?" or "Trying to figure out how long we can ride on our past reputation of greatness"

Well done. =D