So am I the only person to notice this- Apples conference focused on continuity between devices and apps. Yet they still have NO continuity for your apple account. I just installed IOS8 on my iPhone and iPad, then installed Yosemite on my macbook. Even restoring from backup I had to enter my apple ID what seemed like 20+ times between the 3 devices.
Even google I only had to enter once and all their apps pulled my account from another app (or maybe it pulled mail, not sure). Anyways i had to put my ID in for these:

-iCloud
-iOS activation
-App Store
-Bug Reporter
-iTunes Store
-Find Friends
-GameCenter
-KeyChain (just re-enter password to confirm activation)

I think I'm missing one or two.