It's really important for the copy/paste feature to work on a mobile even if you don't have a mouse to select text you want to copy. Apple's implementation is nice. Till Froyo, there wasn't a unified concept of copy/paste feature implemented. But, the Gingerbread has actually changed a few things :) . Copying phone numbers from your mails and email addresses from web pages should be trivial and should involve the least amount of button presses. Prior to Gingerbread, this wasn't the case, but Gingerbread has this "New Feature now".
Here's the link where you can find out more about this.
Some images and videos
You need to double-tap on the text before you can bring up the text selection controls. Once you are done with the selection, single tap on the text copies the selected text to the clipboard, and then you can extract the data from the clipboard. This is really nice. Else, you would have to write a bit of extra code to trigger text selection mode first. This copy/paste selector works on an EditText and on the Browser. I haven't tested it further.
Gingerbread Stuff!!!! **It works on the emulator**.