Update: T-Mobile revised its prior announcement after a miscount of today’s launches. The story has been updated to reflect the change.

T-Mobile USA is rolling out dual-carrier HSPA+ service in 41 additional markets today, including Albuquerque, N.M.; Cleveland and Columbus, Ohio; Sacramento and San Diego, Calif.; Salt Lake City, Utah; and San Antonio, Texas.

With today’s additional launches, T-Mobile has expanded its dual-carrier service to 96 markets. The company says the increased speeds will cover 150 million people by mid-2011.

T-Mobile announced earlier today it would make its faster HSPA+ service available in 47 markets, but later eliminated several markets from the launch. Due to a miscount, the carrier issued an erroneous statement that it would be launching dual-carrier HSPA+ in 42 markets, and later issued a correction stating the expansion would only cover 41 new markets.

The change apparently came after T-Mobile decided to delay the launch of dual-carrier HSPA+ in Pennsylvania.

Six markets in the state, Allentown-Bethlehem, Harrisburg-Carlisle, Lancaster, Scranton-Wilkes-Barre, State College and York-Hanover, were dropped from T-Mobile’s first list of dual-carrier HSPA+ markets set to go live today. Only one city in the state remained on the list, Reading, Penn.

T-Mobile’s single-carrier HSPA+ service currently covers about 200 million people in 184 markets.

Dual-carrier HSPA+ technology doubles the speed of T-Mobile’s existing HSPA+ service by using a software upgrade to aggregate two downlink carriers into a single carrier.

However, only devices equipped with dual-carrier chips can take full advantage of the faster speeds.

T-Mobile currently offers just one device with a dual-carrier chip, the Rocket 3.0 USB modem. Devices without dual-carrier chips will benefit from increased capacity even though they don’t support the faster network technology.