T-Mobile confirmed to 9to5Mac that its 4G HSPA+ coverage will be available to WWDC attendees next week in San Francisco. The carrier said it upgraded its coverage inside the West side of the Moscone Center and now deploys HSPA+ on the 1900MHz band. The timing and location of this update is a coincidence, according to the carrier, and has nothing to do with any large crowd of iPhone users arriving in Moscone. (Ahem.)
This frequency can be used by anyone with an unlocked iPhone, which is convenient for those traveling to WWDC from outside the US. This small scale test will prepare the wireless carrier for a larger roll out of iPhone-friendly, 1900MHz HSPA+ service. T-Mobile expects to support the iPhone and other handsets in a large number of markets by the end of the year.