One of the glaring omissions from Windows Phone 7 when it was first released was cut, copy, and paste. Given that most of the rest of the competition already implemented some form of that function, a lot of users were upset that a "professional" mobile operating system didn't include a professional feature.
An update that would bring WP7 up to speed was originally scheduled for the first half of this month buut according to Eric Hautala, the GM of Customer Experience Engineering for Microsoft, this update should now be hitting devices in the "latter half of March" for what appears to be better quality control.
Back when I reviewed the LG Quantum, I complained that the operating system was still incredibly young. There were many other factors going into my decision, but cut, copy, and paste was still a major one. One other issue is definitely the many app stores, but we'll let Microsoft focus on one problem at a time.[cnet]