If you already have an iphone, your fine, no need to do anything but wait until July 11th. Then upgrade to the iphone 3G and sign a new 2 year deal. Done.
Perhaps I wasn't clear. I know I can do that.
But it looks like I might be able to upgrade on July 10th to a Samsung, say, and sign a contract until July 10, 2010. Then, come back on July 11th, get an iPhone, and sign a contract until July 11, 2010. Basically, I get a free phone (not counting a second activation).