10.3 should work. Go to the Preferences, then Store, and select Automatic Downloads for Music/Apps/Books. Also, you can go to the Apple Store and under Quick Links, you'll find a Purchased link. That'll let you re-download any Music/Apps/Books. It's not really cloud-y yet, but it's a start.

Yes and yes.

Actually, the cost is your click habits. Google is all about getting advertisers to sign on by saying "we have better information on all these people because we house all their data." If you are comfortable with that, that's fine.

Personally, I like Apple's (and for the most part Microsoft) "we don't give a shit about you unless you pay us money." When I stop paying them, I don't have to worry about them keeping any of my data. When I stop using Google products do I have the same guarantee? This is the same argument I use against Facebook.

Huh? iCloud is also free up to 5GB.