late to the party...but,
As was mentioned before, T-Mobile is refarming their 3G spectrum from the 1700 AWS band, to the 1900 PCS band. This will allow any unlocked device, supporting the 1900 spectrum to get HSPA+ (if the device radio supports the +21, otherwise just regular HSPA).
The fact that someone got it in downtown Bellevue, isn't surprising considering T-Mobile is headquarted in Seattle. Logically, I would think they would start the refarm on their home turf and expand by market size after that.
Word on the street is that the spectrum refarm is supposed to be completed by late October, definitely by the start of 2013, as that is when T-Mobile begins deploying LTE on the 1700Mhz AWS band. More markets should begin seeing HSPA+ speeds over the coming months.
I was thinking about signing up with Red Pocket Mobile, because they're an MVNO that uses AT&T. My wife uses it on her Lumia 800 and gets HSPA+, but MMS doesn't work...so I guess I'll stick with T-Mobile EDGE until they refarm Nashville.