I only have a PS2 right now, so I have to vote for that. Although, I wouldn't mind have an XBox or a Wii...
without a doubt the PS series Microsoft cant even get windows right so I dont trust them for gaming Nintendo just has been going downhill and taking the wrong turns in my eyes so I dont care for Nintendo either.
It really is to bad that Nintendo has not been doing well, although, with the release of the Wii, and the incorporation of more popular games (sports and shoot 'em up types), Nintendo may be making a comeback. I definetly want a PS3, but when it comes to the 360 and the Wii -- I really would be happy with either of them.
I chose Playstation because I have A LOT of game systems but out of all of them I have the most fun with my PS2. But Halo is very much awesome, also.
Because xbox didnt exist and playstation was just new, everyone had nintendo or a sega. i grew up with sega