I just decided a few weeks ago I can live without a Wii. I have tons of Cube, PS2, Xbox and Atari games I need to beat before I justify spending $$$ on that sh*t.
I reached the same conclusion about the entire next gen over Christmas. My brother gave me the money for a Wii, and I just bought a great TV I saw on sale instead. I realized that I still need the RE boxed set, Odama (I want to be the guy who beats this game and eventually calls it easy), Lego Star Wars 2 (1 is fantastic), the original Baiten Kaitos, and a few others. Right now I'm playing through Twilight Princess. The number of GBA games that have been/are being released that I need is even larger. And the DS, well, the DS library could still eat me alive. Add in my 2600, now with a speech synthesis unit, and the fact that I need Beggar Prince for the Genny, and I don't have time to play what I own right now.
Thus, I don't see any reason not to wait another year on the next gen. I got the Cube in 2003, beginning my re-entry into modern gaming, and I can't say I feel like I missed out on a lot by buying it then. All that can happen is the libraries for the 360 and Wii will grow while the prices for games, perephrials, and consoles shrinks.