Ugh.
The dashboard - especially the themed ones - look great. But the Xiis? Really, MS. If you make them less Mii-ish and more toward a realistic feel, then I'd be all for them.
Don't take me wrong, I'm not one of those angsty 13 year olds who lock into fetal position if they are seen playing a cartoony game. But wouldn't it make sense if the style and feel of your console interface stays true to the vibe of the majority of your games? So instead of forcing these bubbly monstrosities on us as we wait for our Gears 2 and Fallout 3 to load, give us something that looks more like a person.
What I do like with the Xiis is the idea to take clothing and equipment from the games you play. *That* is a fantastic idea, and instead of making it a small bonus, center the idea around it.
These things have huge potential to expand the gamer picture idea. You could make yourself into a tribute to your favourite games, and show just how good you are with the stuff you're wearing. Don't give us these Xiis, MS, because if people want the Wii experience, they'd buy it. It's cheaper anyways.