Xbox Live Arcade would be receiving exclusive Portal content in the form of Portal: Still Alive need not fret: apparently the forthcoming bonus content has already been alive on the PC for quite some time.
Valve Software's marketing VP Doug Lombardi explained to Gamasutra writer Chris Remo that the content from Portal: Still Alive has actually been lifted and revamped from Portal: The Flash Version MapPack. Portal: The Flash Version was created as a tribute to Valve's puzzle-shooter hybrid, and Flash Version MapPack is simply an extension of that tribute. Download the map pack and follow the instructions to assimilate the Flash game's maps into your copy of Portal.
"So if you're a PC Portal owner who, like me, was feeling excluded by Still Alive's bonus content, fear not: you get to play that content first, and for free," says Remo.