XBOX 360: This will most likely be the best for people looking for online capabilities, they have the most experiance handling an online console. Though not a big seller in japan, so dont expect much support from companies like capcom and konamii. There will be some, but not as much as the other two. On the other hand they have more American support, Bungee for example. Though the graphics (so far) arent too amazing, my comp is more capable than this. Though the first year of a console usually dont have games that really test the capabilities of the graphics engine. So we will have to wait and see. The Launch list had far too many sequals.
PS3: The best thing sony has going for them is there impressive list of third party support. Though the PS2 was inferior graphically to the gamecube and the xbox it was able to be very succesful thanks to the support of great companies. And now that PS3 has the best graphics engine of the three combined with the amazing support they've enjoyed all this time, it should turn out to be an amazing console. Though that graphics enginge carries a hefty price tag with it, making this (most likely, since they haven't announced anything) the most costly of the 3.
Revolution: This one is still very much in the dark. Graphically it should be great (though we have seen no actual screen shots) And the innovative controller has me a bit concerned. It will either be amazing or terrible, Im going to have to wait and see. Im just seeing flash backs of my five year old cousin flinging around the controller of the PS2 in the direction he wants to move, now with this console that is ACTUALLY how it works! I am very interested, and Nintendo has never really let me down in all these years. Though they have never had alot of third party support since the Super Nintendo and this console isnt going to help that. Nintendo itself is usually good enough to crank out a bunch of wonerful game themselves however. Though I dont think Nintendo will ever quite shake its kiddy image. (Resident Evil is leaving Nintendo, so they lose that arguement. Eternal Darkness is a little old, and never got a sequal. and Geist flopped big time) and the flinging around the controller doesnt help the kiddy image.
Conclusion:
PS3: This is the one ill be picking up on the day of its release.
Revolution: Im going to have to wait a month or so after its release to see what its really like. (Or when a Zelda game is released for it)
XBox 360: I said this with the original XBOX, most games feel like they should be for PC, and since I love my PC, Ill stick with it instead of the XBOX