Google (GOOG) this morning announced plans to buy Motorola Mobility Solutions (MMI) for $12.5 billion in cash. Not only does the $40 per share sale price represent a 63% premium (sorry MMI shorts), but also signals that Google is serious about Android taking a bigger bite out of Apple’s mobile device business.

This deal is the 11th-largest M&A transaction announced so far in 2011, according to Thomson Reuters. It also would be the year’s largest-announced deal within the global “high-technology” sector, ahead of Microsoft’s (MSFT) $8.5 billion deal for Skype. Were it to be classified as telecom, it would rank second behind AT&T’s (T) $39 billion deal for T-Mobile.

In terms of Google, this would be the search giant’s largest-ever acquisition (by far). To date, it’s largest deal was for online ad company DoubleClick ($3.1 billion), followed by the 2006 purchase of YouTube ($1.65 billion). Google also was part of an investor group that purchased a 22% stake in Clearwire for $3.2 billion in late 2008. As of last check, Google had around $39.1 billion in cash on hand.