I'm getting an iPhone... I want it bad...
Desktop class Browser/eMail with a phone, camera, iTunes (music & movies/shows), and widgets.
Check the weather on the go, order movie tickets, make reservations via phone, get directions, listen to music while walking around town, then watch a movie while waiting around places. Grab a few snapshots. eMail and voicemail all on one device.
This thing is going to blow Apple's stock through the **** roof.
The Apple TV device will also be killer for people who use iTunes. I prefer CD quality sound for my HiFi setup, but I do purchase singles on iTunes when I want to discover some new material. One of these might join my wireless network soon as well.