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Instagram adds 10 million users in 10 days

Riding a wave of publicity from its billion-dollar purchase by Facebook and after finally opening up to Android, the photo-sharing phenomenon jumps from 30 million to 40 million users.

Not all Instagram photos need a filter. Eric Mack/CNET

Not long after Instagram became available for Android after a long wait, I finally joined the photo-filtering and super-sharing social network last week. Yesterday, while snapping, cropping, and filtering away photos of our kids playing in a Brooklyn, N.Y., park, and at least partly because his curiosity had been piqued by the company's billion-dollar price tag, my brother-in-law finally downloaded Instagram to his iPhone.

It turns out that he and I were just two of 10 million.

That's apparently how many Instagram users have been added in the last 10 days, jumping from a total of 30 million to 40 million. The milestone was first noted on Gramfeed, a Web site for navigating through the world of Instagram, which pulled user ID No. 40,000,000 from Instagram's API -- it's attached to a user named "valentinoelbuti."

If that rate of growth continues, we can surely expect a backlash against the flood of fancy photos. In fact, now could be the time to get in on the ground floor of the next great mobile gold mine -- "actual light" photo apps. How novel!