Sprint isn't the only new addition to Apple's stable of US carriers — Cupertino is continuing its push to get the iPhone downmarket by bringing it to C Spire Wireless, a Mississippi-based regional network (formerly known as Cellular South) with under a million subscribers. An iPhone 4S "Coming Soon" graphic now dominates C Spire's home page, and clicking through lets you sign up to be notified when more details are available — though no date is offered just yet. It's possible that this will line up with Apple's promise of wide availability of unlocked units starting in November, but here's the real question: if C Spire is in, who else will be coming on board? Cricket and MetroPCS are unlikely thanks to their reliance on AWS — a band that the iPhone doesn't support — but others like US Cellular could still get involved.

Source: C Spire Wireless; thanks, everyone!