The Games for Windows LIVE Website announces Microsoft's online gaming service will begin offering digital distribution of games beginning December 15, which will "take full advantage of the unique capabilities offered by the LIVE service," which are not described. Here's a bit:

“With Games on Demand, we didn’t just want to create a cut-and-paste version of existing digital distribution services,” said Mike Ybarra, General Manager of LIVE Engagement Services. “We challenged ourselves to deliver an integrated platform that takes full advantage of the unique capabilities offered by the LIVE service. Our goal has always been to create a seamless online gaming experience for the Windows community, and Games on Demand is a great step toward that end.”

The launch lineup will include recent hits like Resident Evil 5 (Capcom), Red Faction: Guerilla (THQ), and Battlestations: Pacific (EIDOS), as well as new exclusive LIVE-enabled versions of popular digital games like World of Goo and Osmos, distributed by Microsoft Game Studios. All games can be purchased either by credit card or with Microsoft Points. Games on Demand for Windows will be available in markets that currently support the Games for Windows — LIVE service.

Microsoft is also offering an updated LIVE-enabled version of Tinker, formerly an exclusive Windows Vista Ultimate Extra, as a completely free download from the Games for Windows — LIVE client.