I'm not saying it would be completely worth it for Sprint, but hey, they can bet on it if they want ... I actually have Sprint service now, and like it. It's better and faster than AT&T where I am - and cheaper.
No matter what, I won't be getting a Sprint iPhone though ... I'm quite happy with my SGSII.
I just saw the SGSII today and if the new iPhone, whatever it will be called, isn't as good, then I'm switching.