We're still getting over the shock of three of the four nationals suddenly flipping the switch on sub-$100 unlimited plans within hours of each other, but oh, by the way, the onslaught isn't over just yet. Sprint aside, there are still plenty of regionals that don't offer unlimited plans -- along with some that do -- so we expect we're going to see a few more announcements in the coming weeks (or days, considering the pace at which these events have been unfolding thus far). Next to take the podium is US Cellular, revealing a (you guessed it) $99 all-you-can-eat calling plan that will be available to new and existing customers alike, albeit for a limited time. Data and messaging will still require add-on packages to the tune of $25 if you're craving both unlimited bytes and texts, but it still works out to be a decent deal in light of what its primary competitors are offering -- if you exclude Helio, anyway. No word on when exactly folks will be able to sign up for the plan, but US Cellular says details will be posted to its site "soon."

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It's no secret that rural and regional carriers don't enjoy the most amiable relationship with the Big Four here in the States; there's a plethora of reasons why the two groups don't always get along, but whether they like it or not, they're sorta stuck in the same boat. In terms of infrastructure, the national carriers obviously own (or hold exclusive leases to) far more property, leaving them holding nearly all the cards in the roaming game. That leaves the regionals in a bit of a pickle, and once again, they're turning to the FCC for help. This time around, the main complaint circles around the regionals' desire for the national carriers to be required to offer automatic roaming; that is, any carrier of the same technology (GSM or CDMA, that is) should be allowed to roam on their network at a "reasonable" price. Furthermore, they're asking the FCC to to require that any service offered by the nationals be offered to regional carriers' customers as well -- we're not really sure we're following that part of the argument, since it's the big guys that end up footing the bill for the technology build-outs (albeit by charging their own customers in kind) -- but then again, we're all about choice. Predictably, the nationals aren't happy; both T-Mobile and Cingular have come out against the proposal, and we're guessing Sprint and Verizon share the sentiment. It's not known when (or if) the FCC will make a ruling, but the outcome could ultimately determine the fate of some rural carriers relying heavily on third-party infrastructure to provide their user base with service.

[Via The Wireless Report]