Smaller developers have seen more growth over much of 2010, while many of the top titles from leading developers have lost users — in December, though, the losses weren’t so bad.

And, it was also a big month for newcomers to the list with the appearance of Zuma Blitz, It Girl, and, of course, CityVille. Moreover, in case anyone has been on hiatus for a month, Zynga’s new city-builder has found itself at the top with nearly 85 million monthly actives as of today; a plateau breached by FarmVille back in February 2010. CityVille’s growth, however, took less than two months to acquire.

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