The company first launched its $5, all-you-can-hear service last fall, announcing deals with Universal, Sony, Warner and EMI. MOG All Access is a browser-based service that will offer more than 5 million on-demand tracks that, unlike Pandora or other Internet-based radio stations, you can pick and choose from on demand. There is no limit on skipping around songs and if you want to hear a specific song, then you can hear that song.

“You can see the queue, you can jump to anywhere in the queue, when a song comes on the library, you can save it,” said David Hyman, CEO of MOG, at today’s unveiling. “When you listen to Bob Marley radio, it’s not Bob Marley inspired radio. You get Bob Marley 24/7.”

Today’s launch brings this sort of on-demand music delivery to your smartphone. MOG will be launching for Android and iPhone early in the second quarter of 2010. Users will get full access to 7 million tracks on demand, the ability to download music to the phone, MOG radio, 64 ACC+ audio quality with higher quality available by download, for $10 a month.

The demo of the mobile app for Android showed a responsive, full-featured application that allows users to browse through artist discographies, with the ability to add entire albums to the playlist and voice search functionality.

Looking at the iPhone app, we saw a search based app that gives users the ability to play by album, song, playlist or artist radio. An interesting service we’ve only seen with MOG was the slider, which allows the user to give a variable on how they would like MOG radio to work, whether focusing solely on the chosen artist, on similar artists, or somewhere in between. The user can also switch over to look at the album a particular track comes from, play that album and even chose other songs from that album.

The app is not yet available for download on the iPhone and Hyman said that similar services have not had a problem so far. He guaranteed that there would be no problem for the Android, but couldn’t say the same for iPhone.

There is a bit of buzz in the crowd here at SXSW that Spotify CEO Daniel Ek will be announcing the similar music service’s arrival on U.S. shores when he speaks tomorrow at the keynote speech. We also spoke with Michelle Fields, a marketer with Napster.com, who said that a Napster mobile application was also on the way. Napster offers nearly 9 million songs to its users.

“We have a very strong mobile strategy and a mobile application will be unveiled soon,” said Fields.

While we long ago swore off CDs and moved over to the likes of Last.fm and Pandora, this sort of music portability might actually bring us back into the land of the paid consumer. What do you say? Will you shell out 10 clams a month to carry around more music than you’ve probably ever owned in your pocket?

The new platform, for example, will allow users to identify and follow Twitter users on third-party sites without leaving the third-party site. Some of the sites that will soon use this new service include Amazon, Yahoo, Digg, Bing and the New York Times. This, according to Evan, will allow publishers to make sure that their audience is aware of their Twitter feeds, and allow users to follow a site’s or columnist’s feed without every having to leave the site. According to Williams, this will allow publishers to find more followers, and it will also allow Twitter to bring in more users to the site as well as make more non-Twitter users aware of the service. According to Williams, Twitter is launching this service because it wants to lower the barrier of using the service. Given that Twitter’s growth has slowed down in recent months, it only makes sense for the company to try to bring the service to more mainstream users.

While many pundits expected Twitter to announce its ad platform or make an announcement about how the company plans to monetize the service (besides its partnerships with search companies like Google and Microsoft), Twitter did not offer any major insights into its plans today. When asked about the company’s plans, Williams noted that Twitter is not going to go after “low-hanging fruit” and is more interested in creating a sustainable platform.