Wii...
No wait, stay with me. Seriously, I can do this...
Yeah yeah, I'm a PC diehard. I have to stop myself from singing the PCs superior controls, and I hate to do the cheap, "Its not on the list, but I'm saying it anyways because I have strong opinions and am on the internet" thing. In fact, I hate to bring up the PC at all in this conversation, since you didn't mention it, likely for a reason. However, I play a good deal of shooters, exclusively on the PC. I am not short on shooters to play, and playing shooters on PC is part of my life. Playing a shooter on either X Box or PS3 would feel to me like a clunky, unresponsive mess that I could be playing on a PC, and have a much better experience. But then, I look over to my poor neglected Wii, and my copy of House of the Dead, which I have actually logged many hours on. The Wiis controls mean that a shooter on the Wii will actually be completely different from a shooter on any other console, PC included. So I would get far more enjoyment out of a Wii game, because it would give me variety, and even a mediocre but different game on the Wii will give me more fun for a short period of time then a great game where all I can think of is how much I would prefer a computers control scheme.
Yes. I'm pretty sure I just made a good argument to choose the Wii over its competitors. I know. I just BLEW YOUR MIND.