Network testing is hard work. You need to ensure coverage, regular data rates, and spread. That’s probably why T-Mobile happens to be testing their 1900 MHz HSPA+ signal around the Moscone Center in San Francisco just in time for WWDC.
Quoth T-Mobile to 9to5:
While upgrading coverage inside the West side of the Moscone Center, T-Mobile has also deployed 4G HSPA+ service in the 1900 MHz band to test the live network on a small scale. As part of the company’s previously announced $4 billion network modernization effort, T-Mobile plans to launch 4G HSPA+ service in the 1900 MHz band in a large number of markets by the end of the year, which will make our 4G network compatible with a broader range of devices, including the iPhone. NOTE: The time and location of this test is just coincidental.
Arguably the time and location could feasibly be coincidental, but I doubt it. Where better to test connectivity with a band of iPhones than what amounts to the San Francisco iPhone Festival? As mentioned above, 1900 MHz HSPA+ service should be popping up in other locations across the country although I suspect T-Mobile will focus on markets where users are underserved, techie, and would love to spend $30 on T-Mobile’s unlimited data plans.