I like the Beta features that have been released so far:
•Purchase histories in iTunes and the App Store. This allows music and apps purchased on one device to be downloaded to all other devices without having to sync with your computer.
The features that are coming this fall sound good:
•Automatic backup and restoration.
•Syncing documents wirelessly across all devices.
The calendar and contacts apps will also be able to sync wirelessly across all devices, but I’m curious to see how this will work in my situation. My daughter and I each have an iPhone on the same iTunes account with our own calendars and contacts. We’ll see I guess.
I’m kind of indifferent to the photo stream feature.
For mor information see: iCloud