I’ve been thinking about how to take advantage of this iCloud love and am afraid I may have some trouble. My iTunes account is really old and affiliated with an older e-mail address. When I joined .Mac so many moons ago, I created a separate Apple ID, my .MAC account (which later became my MobileMe account). This has never been a problem. I’ve bought lots of apps, books, music, and video with the old iTunes account and the MobileMe account handles e-mail, calendar, and address book.
I am in the same boat. My wife and I share a family account. I’ve used the main ID for years to purchase content on both of our devices, with our family accounts for MobileMe syncing. This has worked great, since MobileMe and iTunes have been separate. However, with iCloud’s smash-it-all-together philosophy, I think I’m going to be going back to my main account for sync, and be buying apps under my wife’s account very soon.
Which bums me out.