We’re not a 100% certain on the specific of this one, but the Samsung SCH-R860U has cleared the FCC sporting Band 12 LTE. That band is used by US Cellular, making this phone destined for that carrier and that carrier only (sorry, Sprint fans).
The question is, does the phone run Android or Windows Phone 8? With the Galaxy S4 right around the corner and Sammy’s slightly cold support of Windows Phone 8, we’d lean on it being another Android phone. But the site Blog of Mobile, who have a pretty decent reputation for finding these filings, claims it sports Windows Phone 8.