With iTunes in The Cloud your iPhone or iPad are free to download music you have previously purchased through iTunes.
New music will be automatically downloaded to your Apple machines.
Apple will release a free, clodbaseret beta version of iTunes for iPhone, iPad, iPod Touch, running IOS 4.3.
This service will automatically upload all pictures taken with the iPhone or iPad to icloud, then the images will be pushed out of ALL HOLDING your other Apple devices.
Are you taking such a picture with your iPhone, you will immediately see it on your IPAD
Photo Stream Storage
With Photo Stream, you can store 1,000 images on each of your Apple machines, and they can be stored permanently in an album.
With icloud you can save each image in the cloud for 30 days.