The carrier says it's prepping high-speed data service for 80 more markets—a move should set the stage for the 3G iPhone, which is expected later this year. Also on tap: plans for an HSUPA rollout, which promises faster uploading speeds for on-the-go laptop users.

In a press release, AT&T crows that it'll have full-on 3G service ready for about 350 U.S. markets by the end of 2008, including the top 100 cities in the country. That should put AT&T on the same high-speed footing as Sprint and Verizon Wireless, both of which launched their respective 3G networks well ahead of AT&T. (Verizon fired up its EV-DO service in 2003, while Sprint turned on its 3G network in 2005; AT&T didn't get started with its HSDPA network until 2006.)

Of course, the news also whets my appetite for a 3G iPhone, which is expected later this year. AT&T beefed up its EDGE network right around the time of the original iPhone launch, so it wouldn't surprise me to learn that carrier's planned 3G expansion is at least partly motivated by the upcoming iPhone update.

AT&T also said that it's ready to roll out HSUPA (High Speed Uplink Packet Access), which promises mobile upload speeds between 500Kbps to 800Kbps (compared to top uplink speeds of about 384Kbps—if you're lucky—on AT&T's current network). That's good news for road warriors looking to upload, say, hefty video files using an AT&T broadband card. The carrier says its HSUPA upgrade should be finished by mid-year.

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AT&T to expand its 3G network to more cities [ComputerWorld]