via DaringFireball.net, There have been analysts and reports that are questioning if Apple can really sell 10 Million units of iPhones this year. I have no doubt they can. They may even beat that number. Jason Snell at MacWorld also thinks so.
Also, just look at some of the amazing things people are already doing with the iPhone development kit: Multi-iPhone Pong, PC Engine / Turbo Grafx Emulator