It turns out the Wi-Fi home phone service that T-Mobile USA launched last summer was just the beginning.

Today, the Bellevue-based wireless carrier is dramatically stepping up its effort to take over your home phone service with a new Internet calling plan debuting in Seattle and Dallas. Plans are to roll out the service in markets across the country after testing.

Internet phone services are a dime a dozen nowadays, including free services, but T-Mobile believes it can lure customers with its quality of service and pricing -- $10 a month for a home phone line with unlimited local and national voice calls.

Called Talk Forever Home Phone, the service requires broadband Internet service and a $50 router with jacks for standard landline phones. You also need a T-Mobile wireless plan costing at least $39.99 per month.

If you sign up, T-Mobile will switch your home phone number to the new service, provide a dialtone and handle all your calls through its network. As part of the signup, it identifies the home address so it can provide 911 location services in emergencies.

This is different from the Hotspot@Home Wi-Fi phone service T-Mobile rolled out last year. That service involves special wireless handsets that can place calls over Wi-Fi as well as T-Mobile's cell network. Subscribers also get a special modem for their home, through which they can make unlimited calls via Wi-Fi for $10 per month, but it doesn't work with traditional landline phones. The service is still available separately.

T-Mobile is starting to sell landline phones in its stores, beginning with a Vtech Dect model that comes programmed with T-Mobile service numbers.

Company representatives talk about this stuff as a "platform" for the home, so expect to see more landline devices and services. In particular, the company wants to make more of the advanced features of mobile phones available on home phones.

"The bottom line is we think it's yet another innovation from T-Mobile that really transforms how people will be communicating in the home," said David Beigie, senior vice president of marketing.

"Landline phone" is probably not the right term. You can use a standard touchtone phone with the service, and the calls will route over your home's broadband line, but they'll be handed off to T-Mobile's network. Instead of Voice over Internet Protocol, or VoIP, this is "mobile technology over IP," according to Britt Wehrman, director of product development.

I'm curious to see whether the $10 pricing will put pressure on Comcast and other major VoIP providers to lower their monthly fees. Maybe it could even push Qwest to offer more attractive voice and broadband bundles.

Beigie isn't overly worried about the slowdown in consumer spending affecting the rollout because T-Mobile is positioning the service as a bargain alternative to wired phone service.

"Given where the economy is in 2008, we think it's an excellent time for people to look at their total communications spending," he said.

It's intriguing and I'll probably give it a try, but I'm probably going to stick with my barebones landline because I want the reliability of wired phone service that can still work during earthquakes, storms, power outages and other events where I've experienced spotty wireless and broadband service.