Using Wacom Bamboo CTL-460 on my iMac and have noticed strange Photoshop CC (and CS6) behaviour since the first beta of OSX 10.9 Mavericks. After a couple of actions with brushes, colours, moving layers and zooming in/out, my PS gets stuck. It shows brush tool, which can move, but I can do nothing till I switch to another app and then get back to PS. Shortcuts don't wort either. There are some messages on Adobe forums about PS shortcuts not working properly on 10.9. I thought it might be a bug in OS with it's all-new memory processing, correlating with PS engine somehow, until I plugged my mouse in... everything worked just fine with it! Double-checked this on iMac and MacBook Pro: all the same on both machines.
So IMHO Wacom driver is definitely causing the issue.
The latest driver update does not solve it.