Contacts: iPad loses
Apple's Contacts app has long been substandard, even as a basic contacts manager. Yes, its ability to sync via iCloud with your other iOS and OS X devices is wonderful, bringing Exchange-like synchronization to everyone. And it has nice touches, like the ability to specify separate ringtones for individuals, to mine your Twitter and Facebook friends for their current contact data, and to link related individuals.
But it doesn't let you create or edit groups (you have to do that on your Mac or PC). Worse, you can't use a group in Contacts in Mail to send a message to everyone in a group -- which is how most of use groups in the first place.