$10 for an app is a lot better than the $1-3 iPhone apps typically go for, and not too far from the $20-30 that desktop apps tend to go for. I think that Apple's trying to lead by example with their iWork pricing. Certainly some apps will undercut that, but I think the truly innovative apps that really do things that can't be done with an iPhone and would be inconvenient on a desktop will be able to command a $10 price tag.