Obviously it's still a rumor at this point, but a probable one. I, for one, hope that it does stay at the current size. Also, the iPhone is truly a beautiful, functional, solid, and quality piece of kit, all-around, with an excellent OS to boot, so I'm staying put regardless.
There are some good (even excellent) aspects to some of the Android-based smartphones out there, but they're just not my thing--often, the hardware is shoddy looking/feeling, or the OS requires a commited process of tinkering, tweaking, and maintaining for optimal utility. That's not my idea of fun, but I get that some people enjoy it.
So, a bigger screen?
On the iPhone, no way thanks. IMO it looks downright silly to see people holding these oversized slabs of kit up to their heads to talk on, or to see them trying to stuff them into their pockets. Not my thing. At all.
Also, I'm really not that interested in trying to make my smartphone into more of a home entertainment system on the go than it already is....if I want to watch videos, movies, or play games--and really enjoy it--that's what my luscious iPad and its exceptional display is for!