Rumorville: iPhone 4S to land on Sprint, T-Mobile in SeptemberYet another round of rumors and analyst notes point toward a late start for the next iPhone, which (so they say) may at last wind up on all four of the big U.S. carriers come September.

First, we’ve got Reuters, which has a trio of unnamed sources who swear that a new iPhone with a “largely similar” look but a “faster processor” than the current iPhone 4 will ship in September, about three months later in the year than the debuts of previous iPhone models.

There’s also a recent note from Jefferies & Co. analyst Peter Misek, who guesses that the iPhone “4S” (and, notably, not the “iPhone 5”) will land in September with “minor cosmetic changes” but “better cameras” and the same dual-core, A5 processor (good for far speedier performance, particularly when the iPhone is juggling multiple apps at the same time) that’s shipping in the new iPad 2.

Misek adds that the new iPhone may well arrive on Sprint and T-Mobile, which sounds reasonable now that AT&T’s headlock on the iPhone has finally come to an end. Such a move would mean that the iPhone would finally be available on all of the big nationwide U.S. carriers (although remember, we may end up with just three by the end of the year is AT&T’s proposed merger with T-Mobile gets a green light).

Meanwhile, there’s still chatter that the new iPhone may arrive with a larger, edge-to-edge display—something akin to the roomy, four-inch-plus screens we’ve been seeing on the latest Android handsets. It’s a tantalizing idea, but something tells me that a bigger iPhone display is just a pipe dream, at least as far as this year is concerned.

Related: IPhone 5′s Big New Features: Sprint, T-Mobile [All Things Digital]
Apple to ship new iPhone in September: sources [Reuters]