There is nothing surprising here. Bigger screen is a plus but I don't see anything here that could entice iPhone 4S users to upgrade. Definitely the iPhone, iPhone 3, and iPhone 3GS folks should give this a shot. Maybe some iPhone 4 owners as well.
Personally, I'm on the fence on this one. I'm waiting for more news to come out before I decide. that's just my personal opinion. The iPhone 5 is a great phone by any measure. Maybe even the best with the Galaxy S III a close second.
Does the above video convince you or not?