I own both a XBox 360 and a Wii.
If you said I could only have one console this generation, I would take a XBox 360 or a PS3 over a Wii. I just think the HD consoles are better for gamers whereas the Wii is better for people who usually dont play games but are interested in them.
I know I'm going to get hammered by lots of Wii fanboys, but I just got tired of the point and click at the screen technology back when it was a fad in arcades and when I picked up a Wii it was loads of fun at first but I eventually got use to it. Add that on top of the fact that I prefer gaming on HD with great graphics plus online gaming (Xbox Live and Playstation Network) really improves gaming experience.
America = Best Gaming Console
Europe = Best Game Developers