XBox 360 and PS3 have more in common with each other than the Wii so, since I dont know much about you, I would say the Wii. You are missing out a lot on XBox 360. If I was in your shoes, knowing my personal preferences, I would buy XBox 360 since I get a lot more out of it than the Wii. I have a lot more fun with Xbox exclusive games like Halo 3, Mass Effect, Bioshock, etc. than I do with Wii exclusive games like Super Mario Galazy and Zelda Twilight Princess. I am also looking more forward to future XBox 360 games (Halo Wars, Alan Wake, Splinter Cell, Infinite Undiscovery, exclusive Grand Theft Auto 4 extra content) than future Wii exclusive (Mario Kart, Brawl).
So just buy whatever you want the most. You came on this forum asking for advice, but I think you already know what you want, or atleast which way you are leaning.
America = Best Gaming Console
Europe = Best Game Developers