Microsoft has announced that the Games for Windows Live Marketplace
will be closing. This will take effect on August 22nd. Afterwards, none of these PC titles published by Microsoft will be available on any marketplace. Third-party games may still available through other digital services, but that will be at the discretion of the publishers. You should contact those publishers regarding the purchase of those games after the deadline.
While not all of these games include achievements, that can be checked by using the TA games list
and changing the platform filter to "Games for Windows Live".
The GFWL service will continue to function minus the ability to purchase new games. You will still be able to play and redownload anything you've purchased prior to August 22nd through the Games for Windows client
Availability of downloadable content for games you already own will differ on a game-by-game basis. Microsoft recommends contacting a particular game's publisher to see if that title will still offer DLC. This is just an opinion, but it might be easier to go ahead and purchase any DLC you want before the deadline.
If you have Microsoft Points tied to your Games for Windows Live account, those are slated to convert to local currency on August 22nd. If the only platform associated with your gamertag is GFWL, this will have a major impact. If that is the case, you'll need to spend those Microsoft Points prior to the deadline. If you have other platforms (Xbox 360, Windows Phone, Windows 8), your MSP will transfer into currency that can be used for purchases on said platforms.
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