Just got in my Wii component cables I ordered from nintendo.com. Only took a little over a week to get them, so if you are waiting for them to come into stores, just go to nintendo.com and see if they are still in stock!
As you would expect, it looks a great deal more sharp and clear... but this is almost a detriment on the "rendered polygon" (or whatever they are) graphics. When I was using composite, everything was blurry; and the sharp, jagged edges on the Mii characters and on other things (like the bowling pins in Wii Sports) weren't as noticeable. These blocky edges jump right out at you with the better detail the component cable provides.
I'm sure I'll get used to it. The good things about the upgrade are increased brightness and contrast, and just in general detail. I just wish most of the stuff was anti-aliased by the hardware a bit... I guess you can't expect that for $250! It is still a real neat device though, I'm glad I bought it.
Anyone else using the component cables yet? Thoughts?