My vote goes to Nintendo. I don't care how much debt they have to deal with, Ninty needs games for its Wii U and this could be the shot in the arm it needs to stay competitive. Sony I'm kind of ok with, they need the games too (Monhun for Vita? yesplz). However, I don't exactly trust them to keep the franchises afloat. Microsoft...Worst case scenario is that they cannibalize Capcom like they did with Rare, and we get properties that're watered down or nothing like the games we expected.*
*feel free to prove me wrong otherwise, I don't follow MS very closely these days
EA...No. Lol. They already got Bioware and Popcap under the knife, they could snuff them out without a second thought and that'd be it. Ubisoft might be more benevolent, but I can't trust them to make interesting sequels. Disney...That would be hilarious if they got Capcom, we could get some pretty crazy ideas...Marvel vs. Disney vs. Star Wars vs Capcom, anyone?
Valve I'm indifferent about, really. I don't see what they'd do with the properties if they actually get them, aside from some silly cross-promo thing with TF2/Half-Life/Portal/etc. We'll just have to see.