I am just realising now how heavily tied into the Apple Ecosystem the whole of iCloud is. It's going to really limit it's usefulness to me. For example: iTunes in the Cloud - requires having purchased your mp3s in on iTunes, which I generally don't do. Photo stream - Okay that's quite useful. Documents in the cloud - Requires iWork, which I don't use. A feature akin to Dropbox would have been more useful. Apps - I don't want all my iPhone apps on my iPad. Books - Limited to the iBookstore which I don't use Backup - Okay that's quite useful. Calendar - I already have cloud ability using Google Calendars, but Apple's version is more restrictive: you can only share your calendar with other iCloud users. Mail - tied to Apple email only, whereas I use Gmail Contacts - Okay that's quite useful. Find my Friends - Useful, but not all my friends have an iPhone so again this feature is restrictive I know Apple try to lock people into the Apple Ecosystem generally, and I consider myself pretty well within this system - but I am not going to exclusively use Apple products (such as iWork) just to get the most out of iCloud.... and that makes it less powerful than it's competitiors such as Google Calendar, Google Documents, Dropbox, etc.