Tebow is probably coming back. Rest of them are gone though.
Georgia has a good recruiting class for QB's coming in, and Caleb King is a good backup to Moreno. Brantley is solid in replacing Tebow, but there won't ever be another Tebow. I don't really know who would replace Harvin, but he's gone for sure I think.
I believe he will just because of his strong senior year. Of course, it also hinges on his combine as well.