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News Summary: Report asserts Twitter is thriving

The Associated Press

TRACKING TWITTER: Twitter's ad revenue will more than double this year to $583 million as the online messaging service delivers more marketing pitches to its growing audience on mobile devices, predicts research firm eMarketer.

GUESSING GAME: It's still unclear how well Twitter is really doing because it's a privately held company that doesn't disclose its finances. Even if they don't totally concur with eMarketer's numbers, analysts generally believe that Twitter's revenue has been accelerating at an impressive rate.

IPO FEVER: The projections are likely to heighten the anticipation for Twitter's initial public stock offering. That probably won't happen until next year, at the earliest.