Not everyone is loving their new iPhone Duo

An open-and-shut case. For most new relationships, two weeks probably isn't enough time to decide if you're ready for long-term commitment. But two weeks with a new phone? You probably know. The iPhone Duo launched just over two weeks ago, and that's been enough time for a subset of day-one buyers who aren't loving the phone to make a decision: It's time to end things. Also, they wanted their…