i hope theres steam keys given to people that bought games on the marketplace, i have arkham asylum and aoe3
I doubt Microsoft would work to do this, although individual games might provide it.
Wait, what exactly is happening and how is it significant?
Games for Windows Live is a service Microsoft had in an attempt to put DRM on PC games, but the methods mainly obstructed players and no body liked it. Many games rely on GFWL for such things as multiplayer service, but with GFWL going down by next year, most games on it will need some kind of update to accommodate. But at least you wouldn't have to deal with them anymore.
The rumor regarding Dark Souls are false; there are no plans as of yet to have the game ported to Steamworks.
In any case, I doubt they'd leave that game hanging. I know nothing about it, but I hear about it far too damn often for me to expect it being dropped.