I will say, in the Wii's defense, that Nintendo has been such a ---smurfy--- performer in the market for the past ten years, that I think 3rd parties really didn't take them seriously before the consoles release. The expectation among 3rd parties was that PS3 was going to explode on the market like an iPod (like PS1 and PS2 did) and that Xbox 360 would continue making gains, further eclipsing Nintendo, and Nintendo would continue it's path toward Sega-land.
So third parties had plans to do a few hack-job ports with half-assed "waggle" controls tacked on, but they weren't going to devote significant resources to doing a bunch of games from the ground-up that wouldn't even be suitable to port to the serious systems because of the vast difference in graphic/processing power and control scheme. This was especially the case because nobody expected that Nintendo still had the ability to make a system that could sell.
So, the Wii really caught developers with their pants down. EA's president has admitted as much publicly. They didn't start seriously making games for the Wii until after it was released, and we all know that a typical development cycle is at least a year, probably closer to 18 months and sometimes far longer.
So, yeah, don't get me wrong. The Wii will have great games for it. But regardless of what developers do, the hardware itself has problems that will always hold it back from what it could have, and what it should have been, IMO.