Social game and app developer Slide has been snapped up by Google for $182 million and is preparing to announce the acquisition Friday, according to TechCrunch. Our own sources are confirming the story — but say the price is actually higher.

[Update: The New York Times says the deal was worth around $228 million.]

Slide is one of Facebook’s larger app developers, with 14.7 million monthly active users and a million daily active users. Compared to Playdom’s 40 million MAU and six million DAU, which Disney just picked up for $563 million, it looks like Google paid a high premium.

As usual, though, there’s more to the story. Slide’s numbers were actually much higher earlier this year; in mid-March, it briefly hit 48 million MAU, while it was well over 20 million for most of 2009. The company has proven adept at promotion and virality, which could benefit a new Google social platform; its social gaming portfolio, however, is not as large as others, and it has lower engagement as a result. Still, as games took off on Facebook, it moved past its popular apps, Top Friends and Slide FunSpace, to release games like SuperPocus and SPP Ranch!.

Those new games didn’t significantly change the picture for Slide, and the company has been fairly quiet this year, not releasing any new titles. A hunt for an acquirer could be the reason behind the apparent inaction.

Whether the price is $182 million or somewhat higher, it’s still likely far short of the reported $500 million valuation Slide had at one point, not to mention the $1.5 billion that founder Max Levchin wanted to exceed (to beat PayPal’s 2002 acquisition by eBay).

But this still looks like a pretty good outcome for Slide. It gets a powerful new owner as a possible alternative to Facebook, which has sometimes acted unpredictably for developers, as with its notifications changes earlier this year.

Google also acquired a game company called LabPixies this year — probably for far less — and invested up to $200 million in Zynga.