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What: Shares of genealogy specialist (Nasdaq: ACOM) are surging today, up by as much as 20%, after the company provided an update on how it ended 2011 and reaffirmed upbeat guidance.

So what: At the end of 2011, it had 1,703,000 paying subscribers, higher than its guidance of between 1,685,000 and 1,695,000 subscribers. Its monthly churn also fell to 3.8%, down sequentially and year-over-year.

Now what: The company expects 2012 revenue growth in the mid-to-high teens. The figures alleviate investor fears that the site's new pricing scheme would dampen sales growth. Piper Jaffray analysts are in favor of the recent changes, saying the site is now easier to use and the longer-term pricing package is appealing.

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