I hope not too many. The iPhone/iPod touch section of the App Store is SO GOD DAMN CROWDED. I hate having to sift through so many crappy apps to find a few gems. I wish they were much tighter with the App Store and only let quality apps through.
Anyways, probably a few hundred. Once again though, I'm hoping that there are less crappy apps released for the iPad since the more expanded UIs will be harder to develop..