I'm going to say NON of them. The competition is good for people who want to play games. If I was forced at gun point to say one company I'd say Microsoft as they are already market leader for the OS in P.C's today.
Thing is the 360 isn't as reliable as it could be considering other systems. Secondly Sony has a high price to buy a games machine(despite other uses for the system). Finally I'm not a big fan of Nintendo now, I just expect to see that name all the time, be in good times or bad (last time I played on a Nintendo system was on the N64 - Goldeneye, MarioKart. Also Super Marioland 2: 6 Golden Coins on the GB, Tetris music got on my Nipples though!).
Good to see this site is still going