iCloud (s aapl) doesn’t fully launch until iOS 5 arrives this fall, but you can check out some features right now. Apple has pushed out updates to the iOS 4.3 App Store, iBooks and iTunes apps that let you check out your purchase history, and setup Automatic Downloads.
In the App Store, go to the Updates tab, and you should see a new item at the very top of the list called “Purchased.” Tapping that link will show you your entire app library, and you can easily see only a list of apps that aren’t yet installed on the device you’re currently using. One tap (followed by your iTunes store password) installs any app in the list on your device, free of charge.
Hit the Store button in iBooks, and then tap the new “Purchased” icon in the bottom menu to find your library. Just like with the App Store, you can see all your owned titles, including those not on your current device.
iTunes has a new “Purchased” menu item in the bottom menu as well, which replaces the Ping icon which no one ever used anyway. It works just like the other two mentioned above, but there’s a catch: iTunes in the Cloud is for U.S. customers only right now, so you won’t even see the icon if you’re in another country.
You can also now turn on Automatic Downloads for any of the above in the Store section of your iOS device’s Settings app. That will mean that, if enabled, when you make a purchase on any device, it will be pushed out automatically to your others, too. You can also toggle whether or not your device will download over a cellular connection — very useful for those with metered data plans.
Apple is also going to release a beta version of iTunes 10.3 that will let you do this stuff on your Mac, too, but the download link hasn’t yet gone live. Let us know if and when you manage to grab it.