It seems that some lucky people will not need to wait until March to get Copy and Paste function on Windows Phone 7. Engadget has discovered that Sprint HTC Arrive already has that function.
I am glad to know that after you copy, you can do multiple pasting of the same content. In this video, it does not show. However, Engadget found that when you swipe to the right, the copied content comes right back. I have not tried it, so I will not be able to know.