Christmas is a time for giving, but it’s also a time for getting – and if you didn’t have an iOS device before the holidays, there’s a pretty good chance Santa placed one under your tree this year. As a result, lots of new gamers hit the App Store on Christmas morning – and OpenFeint has the numbers to prove it.

The popular social gaming network is reporting that OpenFeint-enabled iPhone and iPad games saw a whopping 187% increase in downloads during the four days following Christmas. OpenFeint-enabled Android games also saw a significant though somewhat smaller gain of 73%.

In terms of new users, OpenFeint had more than 450,000 sign ups on Christmas Day alone, and a total of 1.4 million new sign ups during that same four day period.

“We always expect a spike in downloads over the holidays as more people put games on new mobile devices,” says Jason Citron, CEO of OpenFeint. “This year showed an impressive increase as our user acquisition increased almost twofold around Christmas. New devices and free time make for more mobile gaming over the holidays.”

Next year should pose some interesting challenges for OpenFeint, as ngmoco – a company many viewed as their chief rival in the social gaming network space – is poised to release a new platform in conjunction with their new owner, Japanese social giant DeNA. Could their new Mobage network be enough to unseat OpenFeint from its throne?

“Heading into 2011, we expect our 55-million-strong user base to continue showing impressive growth as it has been,” says Peter Relan, chairman of OpenFeint. “We’ve grown six-fold since the beginning of last year and look forward to growing the largest mobile social gaming network.”

2010 was an interesting year for mobile social gaming, but it looks like it may have just been the beginning.