Microsoft has updated its service Games for Windows Live, premiering Portal Version 3.2 for PC gaming platform and integrating the service Games on Demand to it, a similar attempt to distribution service Steam Valve's online content.
As a bonus / celebration for the launch, we Tinker, a nice puzzle completely free (and former Ultimate Extra versions of Windows Vista) available via the site GFWL Games on Demand.
Oh, and: In general, God is more expensive than Steam, has (looots) less variety, and we are limited to the combo Windows / GFWL, so unless someone do your homework in Microsoft, we are completely screwed.