3g and iphone!?!?

So is 3g something you can upgrade to or would you have to buy a completly new phone? I just watched this vid --- a href="http://www.cnbc.com/id/15840232?video=601410342" rel="nofollow"http://www.cnbc.com/id/15840232?video=60…/a ---- on the iphone going to 3g in 2008 and it really pi**** me off because I just bought mine a week ago. So when it comes out do you think they would be able to upgrade the iphones already sold to 3g?