Today (December 21), users who choose to join the Steam client beta will see a new version of their shopping cart when checking out on the Steam store. These users can also mark games as private in the library. The updated Steam Store shopping cart includes some handy new features:
Inline gift purchase-This feature is just in time for the holidays. You no longer need to purchase the game in separate installments and can now buy gifts for multiple friends (and yourself) at once. In addition, the gift information filling process has been simplified, making the checkout process faster;
Shared shopping cart across multiple devices-The contents of your shopping cart will be with you on all devices that are logged into Steam. Please note that during the testing period, the shopping cart will only be accessible in the beta client;
private purchase-The privacy of a game needs to be considered before purchasing, so the updated shopping cart allows you to mark a game as private before checking out.
private games
Steam has long offered multiple levels of privacy settings for your Steam profile and your entire game list. However, there are times when a user may wish to keep the few specific games they own private.
Starting today you can make certain games private so they won't be visible to anyone but you where they would otherwise appear. Others won't be able to see that you own the game, play the game, or see how much time you play or what you do with the game. This extra layer of control allows you to make most of the games in your library visible to your friends, so they can see what you're playing and join them, while making a few games visible only to you.
How do I mark a game as private?
There are three places where you can mark a game as private: in the shopping cart, in the game list (accessible in a web browser), and in the Steam client library (game page > Manage (gear icon) > Manage)