Scott, I wrote several posts on that subject. Basically, I feel that Apple will open up development to selected developers during WWDC, meaning soon after Leopard is out. Should a high-end iPod or low-end OS X tablet come out at that time (IMHO 99% certain to happen), that would make a nice sandbox/developer platform, and they could certify selected apps for that to migrate to the iPhone.
by Rainer Brockerhoff — Jan 15