However, even with the masses descending upon Las Vegas this week, Cricket has decided to delay the Muve music service and the launch of its first Muve-compatible phone.

Cricket had hoped to launch service in Las Vegas this week along with a number of other markets later this month.

Under its revised time frame, Cricket plans to launch the service in Las Vegas later this month, add nine more cities in February and roll it out to the rest of its markets this spring.

Although all the necessary licensing is in place, Cricket spokesman Greg Lund said that the company needed the extra time to ensure all of the software bugs were ironed out before it started asking customers to pay for the service.

“It’s got to be just perfect,” Lund told Mobilized in an interview at CES in Las Vegas.

The company, best known for its prepaid phones, is offering a new service called Muve Music, which includes the cost of unlimited music downloads as part of a $55 monthly cellphone plan that also includes unlimited talk, text and Web. Basically, Muve adds about $10 to the cost of the monthly cellphone tab (which, incidentally, is about what one can expect to pay for the typical subscription music service).

The music is downloaded directly to the cellphone and is accessible as long as you remain a subscriber. From a technology standpoint, the service works by transferring the music to a secure partition of a 4GB digital memory card in the phone; Cricket says that partition can hold about 3,000 songs.

Cricket is launching the service next month with a single compatible phone–a color touchscreen feature phone known as the Samsung Suede, which will sell for $199. The service will first be available Jan. 6 in Las Vegas, with about 10 of Cricket’s other markets due to come on board later in the month.

What makes the service interesting is the approach–there is no tie to a PC whatsoever. Music comes to the phone, lives on the phone and is managed on the phone. In an interview, Cricket Vice President Jeff Toig said the service is geared to Cricket’s base of customers, many of whom don’t have a PC and broadband connection. It also allows them to get their music the way they do their other cellphone services–by paying in cash at the company’s retail outlets, thereby eliminating the need for a credit card.

The downside, of course, is that the music can only be played on the phone, though the phone can connect to a car stereo or external speakers over bluetooth or via a 3.5mm cable.

On the plus side, Muve doesn’t add much to the cost of a cellphone plan and eliminates some of the complexity traditionally associated with digital music. In addition to the ability to download and play tracks from all four major music labels, Muve subscribers can set any track to be either a ringtone or ringback tone (the music heard by callers while they are waiting for someone to answer).

Nokia tried a somewhat similar approach with its “Comes With Music” phones, which debuted in 2008. In that program, the cost of the music subscription was included in the price of the phone rather than in the monthly cellphone bill. Others, such as SpiralFrog, have tried to create services relying on advertising to subsidize the cost of providing music free to the end user.

Toig said that his customer base is one that typically isn’t downloading music from iTunes at 99 cents a pop, but includes a fair number of people that illegally download music from file sharing services.

The new service, he said, allows them to have a better experience without having to spend much more than they already are, while giving the record industry a chance to reach digital music customers they are largely missing out on today.

Unlike other services, which Toig said bank on the fact that people have access to a computer, Muve tries to make it easy to discover and download music directly from the phone. Customers can subscribe to curated feeds of music that get automatically updated, as well as find and download albums by name. A built-in social network allows them to see what their friends are listening to (assuming they also have a Muve-compatible phone).

“Nobody has done mobile music right,” Toig said.

Cricket won’t say how much of the incremental $10 in monthly revenue it is getting goes to the labels, but Toig said part of the bet is that Cricket will be able to reach customers that it otherwise could not.

“We’re obviously not doing this for a few percent,” he said. “We think this has appeal beyond our base to segments Cricket has not appealed to before.”

Where? In Sweden, of course, which is where Spotify started, and which acts as a sort of test lab/best-case-scenario provider for the service.

The company has announced a two-year deal with Telia, a European telco/Internet service provider, “to work together developing Spotify’s music service for computers, mobile phones and eventually TV as well.” No details about what that TV service might be, but the companies say a mobile offering will be available for Swedes within a “few months.”

That’s interesting, since Spotify already has a mobile offering: Subscribers to its premium service can use the company’s iPhone app, which Apple (AAPL) approved last month. No description of how the new service will differ.

It’s also worth noting that this is Spotify’s second deal with a Swedish ISP. It already has a linkup with Bredbandsbolaget, owned by Telenor, a Scandinavian telco, which allows users to bundle their subscription fees with their Internet bills.

It’s also the only territory where the service has a bundling deal, and industry observers think that tie-up has a great deal to do with the company’s much talked about success there.

Everywhere else, though, Spotify remains a work in progress. It claims 5.5 million users, but as of last month only about 100,000 of them were paying the company a monthly fee, according to people familiar with the service. It is currently trying to break into the U.S. market, but has been mired in discussions with the big music labels–the same ones that have licensed the company in Europe–for months.

For more on the company’s plans, see this interview Kara Swisher conducted with co-founder Daniel Ek last month: