The only thing I want to paint my XT with is
MUD! I've never been much on washing bikes anyway, (rain rides count as a wash, right?), but it's going to be bad enough riding off pavement with a new bike, if you paint it and make it all pretty you'll never want to have fun with it. What's next? Pinstripes on your crash bars? Polished skid plate? ???
I'm really considering picking the bike up from the dealer, riding across the parking lot to some dirt, getting off the bike and kicking it over for a dirt nap, (in full view of the dealership), just to get that first drop out of the way. Bonus, find out what gets broken, then fix it so it won't next time. Only down side to this is I'd really want to have all the protection bits on the bike prior to the dirt nap testing and I'm too cheap to pay the dealer to do that when i can do it myself, (and will know it's done right).
Ah, heck, paint it white, it will look COOL!
Yellow is just a "look at me" color.