A Steam Community Group Announcement has details on a new patch that's now available for the Windows edition of Batman: Arkham Knight, the superhero sequel (thanks Wookiestick). This includes "gameplay fixes and stability improvements" along with other changes. Here are the details:

• Fixed some issues with stars being awarded or lost incorrectly in specific AR Challenges
• Improved target prioritization during combat
• Restored heavier rain during the opening section of the game
• Fixed missing rain effects on a few remaining player character skins
• Miscellaneous gameplay fixes and stability improvements
• Fixes to some keyboard and mouse prompts after being rebound
• Made frame times more consistent for 60hz monitors running at 30fps with VSync enabled
• Previously equipped gadgets can be selected with keyboard and mouse again after restarting an AR Challenge
• Fixed the default key binding for Harley’s Snare gadget
• Batgirl’s Remote Hacking Device can now be properly selected with keyboard & mouse in AR Challenges
• Minor performance optimizations for certain combinations of hardware
• Fixed keyboard & mouse controls that did not function in DLC AR Challenges when no previous save data existed
• Quick Photo Mode can now be triggered with keyboard and mouse controls when using the Batmobile
• Special Combo Takedowns can now be performed with Quickfire Gadget binds if they were rebound
• Fixed graphical corruption that may occur after Alt-Tabbing
• Improvements and corrections to some localized text
• Added new Classic Harley Quinn skin for use in AR Challenges & the Harley Quinn Story Pack
• Added Arkham Knight as a playable character for AR Challenges & the Red Hood Story Pack
• Added support for December DLC content