" BioShock Infinite and 10.9 Performance on NVIDIA
Please note that there is a performance drop that occurs for BioShock when running in 10.9 on an NVIDIA card.

General Information:

Maxing out the resolution and graphic settings (using high presets) has a noticeable difference in performance.

• On the 640M and 650M these settings make the game frame rate feel slower and even hitches more.
• On the 660M, 675M, 680M, 750M, 755M, and the 775M the game is playable on any setting, but the user may notice that the frame rate is lower than on 10.8.

Default settings run at an acceptable frame rate on every machine in 10.9.

• We have even tested maxing the resolution and felt that the performance was acceptable.
• We also tested making the resolution and using medium default graphic settings and everything still felt like it was ok.

The key thing to note here is that if you max out the available graphic settings and resolution, you may not have as good of an experience on 10.9 as you did on 10.8. We are looking into possible solutions with Apple."

If it's due to an Nvidia driver issue hopefully they'll fix it in an update. (If it's that simple.)

Aspyr looking for Feedback on OS X 10.9 Mavericks Game Issues:
In addition to the above, they also have another post asking for feedback on OS X 10.9 gaming issues in general. (With games they support/sell.)

"Potential Gaming Issues Under OSX 10.9 (Mavericks): We Need Your Help!
Each time a new operating system is introduced some product abnormalities may occur. We make best-efforts to test our catalog on each seed and thus far our sweeps have not reveled any significant gaming issues. But you, our audience, are a much better representation of the varied hardware configurations available, and we need your help!

If you experience any issues once you upgrade to Mac OSX 10.9 (Mavericks), please contact our support team with product and system information. Issues could include:

• screen flickers
• image distortion
• game crashing
• freezing
• general gameplay issues

Please open a support ticket on support.aspyr.com and attach your system profile to your ticket. This important step will help us evaluate if the issue is isolated to a single hardware profile or is being experienced across multiple machines.
We appreciate your help and feedback."

Later a note was posted about uninstalling games in OS X 10.9:

"There is a known issue with uninstalling games from the launchpad in (OS X) 10.9
Please note that uninstalling a game from the launch pad deletes the game as well as its containers folder? This is new with Mavericks and might cause some customer headaches/confusion.
Manually dragging the app icon to the trash keeps their respective saves, config files, etc stored in the Containers directory which, most times, is preferred by users.
-Jason (Asypr Support)"

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