T-Mobile just flipped the HSPA+ switch on four more cities. If you live in Des Moines, Iowa; Gainesville, Fla.; Panama City, Fla.; Monterey, Calif.; or Savannah, Ga., you have reason to celebrate, especially if you have one of T-Mo's newfangled 4G devices like the HTC myTouch 4G, Samsung Galaxy S 4G, T-Mobile G2 or the upcoming Dell Streak 7 or G-Slate. For everybody else, well, poke along at 3G speeds, if you've got 'em. [T-Mobile, full list of 4G cities]