In May of 2009, AT&T announced that it would begin upgrading its 3G network in some areas to new HSPA 7.2 Mbps speeds. AT&T also said at the time that it planned to double the spectrum that it allowed for 3G service in some areas.

The first six cities in the country to get the new faster HSPA 7.2 speeds from AT&T were unveiled in September 2009 and included Charlotte, Chicago, Dallas, Houston, Los Angeles, and Miami. Today AT&T has announced that its software update of all nationwide 3G cell towers to support the HSPA 7.2 service has been completed. The software update has the nationwide network of AT&T towers ready for the faster data speeds.

AT&T reports that it decided to expedite the roll out of the software update to provide better customer experience and improve consistency in data sessions. The software update sets the table for the 7.2Mbps speeds to come later in 2010 and in 2011 as additional backhaul connections are added to support the higher speeds.

“We are focused on providing our customers with the industry’s best combination of mobile broadband speed, performance, coverage and available devices,” said John Stankey, president and CEO, AT&T Operations, who announced the network updates at the Citigroup 20th Annual Global Entertainment, Media & Telecommunications Conference today. “As we light up new backhaul connections across the country, we’re able to deliver a meaningful 3G speed boost for millions of customers who are already using HSPA 7.2-compatible devices. At the same time, we’re also looking to the future with these backhaul enhancements, which will support our move to next-generation LTE technology starting in 2011.”

AT&T says that it already has ten HSPA 7.2 devices on the market today including the highly popular iPhone 3GS along with nine others. More HSPA 7.2 handsets are in the works for 2010. The backhaul updates for the AT&T towers are a key part of the transition to LTE that is coming as well.

“Even as we look forward to LTE, 3G will be the predominant mobile broadband network technology worldwide for smartphones for the next few years,” said Stankey. “AT&T’s strategy will deliver faster 3G speeds over the next two years, while also allowing us to build the foundation for the LTE future.”

AT&T still plans to begin trials of LTE service in 2010 and will begin LTE deployment in 2011. With the six cities previously mentioned being the first to get the HSPA 7.2 speed upgrade that includes the additional backhaul connections needed for LTE, odds are these will also be the LTE testing areas and among the first to get LTE service when it is available.

That’s why I’m intrigued by Sezmi, a TV service that’s announcing that it’s rolling out to its first real customers (in Los Angeles). The service aims to provide a more personalized, Net-savvy, inexpensive alternative to cable and satellite – complete with the real broadcast and cable channels you can’t get from Apple TV, Roku, or Vudu. It does so via a 1TB DVR/set-top box that provides access to three types of TV sources: broadcast stations, cable channels, and Internet content. (It snags the first two kinds over the air, via a powerful antenna in a box that looks like a loudspeaker: Sezmi simply grabs local broadcast channels as is, and the company is leasing spectrum from local broadcasters to transmit cable channels – including both standard-def and HD.)

Sezmi’s lineup of cable channels isn’t as expansive as a higher-tier package on cable or satellite, but it’s got Animal Planet, Bravo, Cartoon Network, CNN, Comedy Central, Discovery, MSNBC, MTV, Nickelodeon, Oxygen, SyFy, TBS, TCM, TLC, TNT, VH1, and more. The most notable omissions are sports channels–I don’t see ESPN or others in the lineup–and premium movie channels such as HBO, Showtime, and Cinemax. But Sezmi does offer a store that sells and rents movies and TV shows from a library of thousands of titles (powered in part by Roxio’s Cinemanow). You also get access to Internet video such as YouTube and podcasts.

The service is touting itself as Sezmi uses its roomy 1TB hard disk to give each member of the family his or her own personalized on-demand TV experience: Grownups and kids both get program guides tailored to their watching habits that weave together broadcast, cable, and Internet shows, including ones on the DVR and ones showing at scheduled times.

The company gave me a sneak peek that included a demo of its interface: It’s impossible to come to definitive conclusions without hands-on time, and I’m particularly curious about how seamlessly it knits together its disparate sources of content. But from what I saw, it looks reasonably promising.

How much will you pay for Sezmi, and where will you get it? Its goal is to undercut the cost of cable: Basic service that only includes broadcast stations will go for $4.99 a month, and a broadcast/cable package will cost $24.99 a month. A la carte movies and TV episodes are extra. You’ll either buy the box and antenna (for $299, $50 more than TiVo charges for a DVR with one-sixth the capacity) or rent it. Once the service rolls out to more regions–which the company says will happen soon–it’ll be available both at retail stores and through service providers such as medium-sized phone companies and DSL ISPs.

I generally feel like I’m watching maybe five percent of the channels my Comcast cable service gives me–and among the very few that I’m not willing to give up are CNN, MSNBC, and TCM. So Sezmi, which has all those stations, sounds like a plausible alternative–and even if I had to plunk down $299 for the box, I’d make it up pretty quickly in the money I’d save over cable.

Cable and satellite TV subscribers: Are you basically happy, or does Sezmi sound alluring?