Scooter Braun
CEO, Schoolboy Records and SB Projects;
Entrepreneur in Residence, Universal Music Group Global Creative Investment Program

All things Justin Bieber and SB Projects, with a healthy dose of industry philosophizing, inspirational messaging and "I love my life" tweets, such as: "Just got off the phone with @justinbieber while he is in Japan -- he asked me if people are liking #BELIEVE - YES MAN!!"

Elizabeth Brooks
CMO, Buzz Media

In-the-know digital and social posts from longstanding digital expert (who worked at Napster back in the day). Sample tweet: "My pick for a super-hot company, @mixpanel, now has user-centric analytics -- will generate real insight into your app user base."

Jennifer Bull
Sr. Marketing Manager, Sony Music U.S. Latin

Bull's tenure at Sony makes her one of the most resourceful marketing managers in Latin music. Although she works with a diverse pool of talent from pop to rock, she has helped usher in such rising stars of regional Mexican music as Gerardo Ortiz ( @gerardoortiznet), Martin Castillo ( @MartinC_oficial) and @CuatesdeSinaloa.

Jim Butcher
Head of Communications, Spotify

If you're into streaming (or soccer), you've come to the right place. Playlists (and retweets of artist playlists), naturally, along with a steady flow of Spotify news and "mythbusting."

Noah Callahan Bever

Hip-hop insider and content king of a network of sites that claims 57 million unique visitors, N_C_B commands the attention of some of the most hyper-connected of the young urban (predominantly male) audience. He talks a lot of hip-hop, street style and… hip-hop in a constant stream of @'s to industry friends and staffers as well as those far beyond the Complex walls. Expect plenty of self and brand promotion as well as links to throwback hip-hop classics, often via Spotify.

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Mike Caren
President, Worldwide A&R, Warner Music Group

Not the most prolific tweeter, but when he does take to the tweets, Caren, a former DJ and producer and now recently president of worldwide A&R at WMG, calls the big records as he sees them and gives credit where credit is due, even to those on different teams.

Steve-O Carless
Lifestyle Marketing and Promotion Director, Island Def Jam

Aside from his post at Def Jam, Carless is the co-founder of Best of Both Offices, a lifestyle blog that covers established and emerging artists in hip-hop. On Twitter, Carless mixes Def Jam promotional tidbits with weekly links to unsigned artists worth spotlighting, adorned with the hashtag #UnsignedTuesdays. Follow, and you might find a few gems.

Rosanne Cash

Scenic photography from life on the road is mixed with topical conversations about politics and art on Cash's frequently updated account. One minute, Johnny Cash's eldest daughter will be dreading the "squillion degree" weather in New York City; the next, she'll be making declarations on gun laws and climate change.

Bill Chasen

Also the creator of real-time analytics service Chartbeat and chat service Firefly, Chasen lives at the nexus of music, tech and social. His Twitter bio says it all: "I like to create art. Some things you hang on the wall, others you log into."

Mary Hk Choi
Senior Editor, MTV Style; Columnist, Wired

Style and snark, snark and style and a barrage of tweets aimed at the hippest of New York's hippest media circles. Sample tweet: "If the gaultier exhibit teaches us anything it's that the man has had EVERY idea ever. And that the striped umbrellas at the gift store=$140"