That would be kinda cool I guess but which fighting style would they use. Would they use killer instincts style of play of would they use Mortal Kombats?

I'd rather see separate games first. A bit of healthy competition rather than wasting a couple of years bunging a new set of characters into virtually the same game engine as last time. Again.

what i'd like to see is a fighting game that takes players from many fighting games and only takes one or two characters from the mk universe that would simply be called "fighting all stars". i would like to see a game sort of like the fighters megamix for saturn. so maybe sub-zero and scorpoin could be in a game the includes characters from many games.

i.e megaman vs subzero
i.e scorpion vs Ryu

Eyedol Vs. Goro -- Fulgore Vs. Sektor -- Jago Vs. Liu Kang -- Glacier Vs. Sub-Zero -- Cynder Vs. Scorpion -- Spinal Vs. Shang Tsung (since they can both morphe into other people) -- Kitana Vs. Orchid -- Combo Vs. Jax would all be awesome fights to remember. Doing Ultra's with the KI people and doing Brutalities with the MK people.

Midway vs. Capcom would be cool too. The 3D renders of MK shouldn't be a problem; I mean if they can turn Jill Valentine from 3D to 2D (Resident Evil Jill in Marvel Vs. Capcom2) then they can do it with all the 3D Mk characters with no problems.