What console do you play multiplat games on?

I'm mainly talking about games like The Orange Box and COD4. I'm probably going to get them sometime and I want to know what console everyone has them on. I'm thinking about getting them on PC, since I prefer mouse/keyboard for FPS games, but if everyone has it on PS3/360 then I might as well just wait until I get a PS3 or 360. And also which would you prefer to have it on.

So could you please let me know what console you have it on. Or, better yet, could you please tell me if there is a website which says how many people are playing on what console? Thanks.

...whichever system the game is best on. If the game is basically identical across all platforms, I just go for the system that has the controller I prefer.

In the case of The Orange Box, go with either the Xbox 360 or PC. With CoD4, I'd go with the PS3 version, but it doesn't matter too much for that one.