T-Mobile is currently lagging behind its competitors in terms of wireless networks. This carrier is still focusing on its 3G network while its rivals already preparing for a commercial release of the new 4G wireless networks. However, T-Mobile's growing HSPA+ network is actually one of the fastest data network in the US.

T-Mobile's HSPA+ network is called a super 3G network because it offers speeds that are superior to a typical 3G network. HSPA+ is essentially a software upgrade to T-Mobile's existing 3G infrastructure. It will be able to theoretically) pump out speeds of up to 21 mbps.

Well, T-Mobile has claimed that HSPA+ networks are faster than Clearwire 4G WiMAX networks. Yeah, that's right, it's a WiMAX vs HSPA rivalry. The WiMAX vs LTE competition is not the only scenario in the race for wireless speed.

Some tests indicate that T-Mobile  HSPA+ network  clocked average download speeds of 1220 kbps in New York City. Some testing locations saw speeds as high as 3.5 megabits per second which are similar to what you might expect to see from new 4G networks.

T-Mobile is currently expanding its HSPA+ network. The network is currently operational in Philadelphia, New York, New Jersey and D.C., with new markets, including L.A., launching in the near future.