4G is in the air! Or, at least for T-Mobile, 4G speeds are in the air. While T-Mobile isn’t technically allowed to pitch their HSPA+ network as 4G, its speeds can exceed that of the networks that some carriers (read: Sprint) have been toting as 4G for the last few months. This morning, T-Mobile is officially debuting their HSPA+ network in 15 new cities, from Los Angeles, CA to New Orleans, LA. While a handful of places — New York, Philadelphia, Vegas, and Memphis, to name a few — are already blanketed in T-Mobile’s latest radio juice, the new roster is pretty impressive. If you’re in Atlanta, Houston, Seattle, Tampa, Orlando, Pittsburgh, Charlotte, Greensboro, Winston-Salem, Oklahoma City, Tulsa, New Orleans, or Charleston, fire up your device and give it a speed test — chances are, you’re surrounded in 4G(ish) radiowaves right this second.