Twitter references seem to be popping up everywhere. From news shows to sitcoms such as The Big Bang Theory, there’s no denying that the service is finally going mainstream. And now even celebrities are joining in.

Some seem like your typical Twitter users, posting about whatever crosses their minds, while others use their accounts as a promotional tool. Here are over 25 celebrity Twitter users, from actors to writers, musicians, and more.

What do you think of celebrities hopping on the Twitter bandwagon?

Actors

Brea Grant - Plays Daphne, the super speedster, on Heroes.

David Hewlett - Actor best known for his role as Dr. Rodney McKay on Stargate Atlantis.

Janina Gavankar - Played Papi on The L Word. Also appeared in both Barbershop movies.

Kate Hewlett - Sister of David Hewlett. She also played his sister on Stargate Atlantis.

Stephen Fry - Well known British actor, comedian and narrator.

Wil Wheaton - Best known for the role of Wesley Crusher on Star Trek: the Next Generation, Mr. Wheaton has become well known for his passion for all things tech.

William Shatner - This well-known actor has only posted one update as of this writing.  Seeing as he has a YouTube account that is being updated frequently, he may return.

Musicians

Brett Gurewitz - Guitarist for the band Bad Religion, songwriter and record producer. Also owns Epitaph Records.

Britney Spears - With the launch of her new album, Ms. Spears is embracing the Internet with a redesigned website and the launch of a Twitter account.  You can read more about this in Searching for the Real Britney in ‘therealbritney’ here on Mashable.

DaveJMatthews - Best known as the lead vocalist, songwriter, and guitarist for the Dave Matthews Band, Dave Matthews is a Grammy award-winning singer-songwriter and musician. He updates fairly regularly.

Jonathan Coulton - Well known on the Internet for self-promotion and writing songs with geek themes.

MC Hammer - Musician, pastor, rising Internet celeb - it seems MC Hammer pops up everywhere.

Patrick Wilson of Weezer - The drummer from the band Weezer posts infrequent updates to his account.

Sara Bareilles - Sara Bareilles is a singer-songwriter and pianist that posts updates from her tour and elsewhere.

Politicians

Barack Obama - Senator from Illinois and Democratic presidential candidate.

Chuck Grassley - Republican senator from Iowa.

Hillary Clinton - Senator from New York, former presidential candidate for the Democratic party and the former First Lady.

James DeMint - Republican senator from South Carolina.

James Inhofe - Republican senator from Oklahoma.

Joe Biden - Senator from Delaware and the current Democratic candidate for vice president.

John McCain - Senator from Arizona and the Republican Presidential Candidate.

Tech Celebrities

John C. Dvorak - A columnist writing about technology since the 1980s.

Leo Laporte - Leo Laporte has been a long time commenter on technology issues and host of numerous TV shows and podcasts.

Major Nelson, Xbox Live Director of Programming - Major Nelson is the gamertag of Larry Hryb, the director of programming over at Xbox Live.  He gives out codes and other information on his account.

Mike Krahulik of Penny Arcade - One of the authors of the popular webcomic, Penny Arcade.

Robert Scoble - Needing no real introduction, Robert Scoble is one of the best known tech bloggers on the Web.

Scott Kurtz - Creator of the popular Web comic, Player vs Player.

Tony Hsieh, CEO of Zappos - Zappos is everywhere nowadays, even at the bottom of shoe trays at airport security, so it only makes sense they would also pop up on the most popular microblogging service.

Writers

Diablo Cody - Ms. Cody won an Oscar for her film Juno, and has become a popular, though sporadic, poster on Twitter.

James Gunn - Writer, director, actor, musician, James Gunn is a jack-of-all-trades and a prolific Twitter user.

Warren Ellis - Popular comic book writer of series such as Transmetropolitan.

We may not be celebrities, but be sure to follow the Mashable team on Twitter:

Pete Cashmore

Adam Ostrow

Stan Schroeder

Mark Rizzn Hopkins

Sean Aune

Paul Glazowski

Sharon Feder

Tamar Weinberg

Adam Hirsch

Brett Petersel

Karen Hartline

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…if you have a Nokia N800 or N810, that is. That’s right, the mobile version of Firefox (which would have had a far greater impact had it come before the advent of mobile Safari) is now available as an early developer alpha (v.1.0a1), works (well) only on the aforementioned Nokias, and goes by the name of Fennec. If you’re the curious kind, there are versions for Linux, Max OS X and Windows, so you can test out those too; installation instructions and release notes are available over at the official site.

What’s there to see? Some of the interesting features included in this alpha are bookmarking and tagging, the inclusion of Firefox’ awesome bar (its awesomeness still being the subject of discussion), tabbed browsing, easy search, zooming, password management, popup blocking, and an easy way to clear private data. It doesn’t sound bad at all; still, it’s an early alpha version; I recommend you save yourself the trouble of installation and check out the presentation in the video below.

Fennec Alpha Walkthrough from Madhava Enros on Vimeo.

—Related Articles at Mashable | All That’s New on the Web:Mozilla Gets Touchy and Feely With Firefox ‘Fennec’ MobileMozilla to Go Mobile, Launch Firefox for Cell PhonesShare Bookmarks Between Your PC And Mobile With OperaFirefox 2 Security Fixes ReleasedNews Corp’s Jamba Loses CEO400 Million Firefox DownloadsMozilla: Would You Like a Virus With That Add-on?

Source:Mashable!

iLike and TuneCore may be a bit late to the monetizing music party, following sites like Grooveshark, but they have now arrived in full force. Today TuneCore and iLike announce that indie artists will be able to earn money from people listening to and sharing their music via iLike.

iLike is poised for great leaps in success right now. They are rumored to be the favorite music application for FaceBook to endorse as its preferred app for a FaceBook music integration. Not only that, just this past summer iLike made several improvements by offering free streaming of full tracks and integrating an ad platform into their service, showing a keen eye for monetization and long term growth.

Why partner with TuneCore? iLike is more of a social discovery service for music, and TuneCore is a music distribution service. Together they have the ability to help artists make money off of the songs that they write and sing when people listen to them.

More and more services are going to this new digital revenue model in the music industry. Instead of waiting to be picked up by a label, going to the studio, going to press, advertising and going on tour, this new model allows artists to make money in real time, simultaneously with a tour, merchandise sales, CD pressing and more. No more waiting for big business to catch up. It also offers a bit of real time feedback - if you aren’t going to be popular, your level of digital revenue will reflect that immediately instead of waiting to release a CD that might fail.

What does the this proliferation of turnkey music monetization services mean for musicians? It allows them to basically be their own label. Artists submit their music via TuneCore and then it is played via iLike, and everywhere iLike is found. This includes FaceBook, embedded playlists on blogs, and more. TuneCore also gives artists access to iLike’s entire network, including hi5, Bebo, Orkut and more. TuneCore also serves music to sites like Rhapsody, Yahoo, MTV and Amazon. Artists then keep 100% of the money they make via the service.

Ali Partovi, CEO of iLike, said “As the music industry continues to reinvent itself, we believe it’s critical to offer independent musicians equal opportunity alongside major-label artists.” And he’s right - this online network created for artists by combining the reach of iLike and TuneCore enables a band or artist’s music to be heard in as many places as it would be it released by a major label. That’s a huge advantage for an artist to make money doing something they love, and isn’t that every musician’s dream? To get paid to do what they love?

—Related Articles at Mashable | All That’s New on the Web:iLike Launches New Tools for ArtistsiLike, Billboard Team Up for New Music ChartsHear The New R.E.M. Album on iLike Before it Hits the StoresiLike Sees Exponential Growth with Facebook AppiLike Worth $50M, TicketMaster Buys 25%Ringtones on iLike, Powered by ThumbplayBono Unveils Unreleased Track via iLike