I'm running Houdini Indie on a new Mac Pro with Mavericks 10.9.5
I'm getting a lot of crashes where the whole machine freezes.
I'm not doing anything particularly exotic. Playing with POP/DOP's etc.

Is there anything I can do/look out for to improve stability?

Upgrading to 10.10.2 helps tremendously. Apple's graphics driver updates are tied to their OS updates, unfortunately.

I am also experiencing a similar issue. When I quit Houdini, sometimes it disappears from the process list however finder still thinks that Houdini is running. And when that happens Houdini icon won't die and it is listed in the Force Quit list of finder as a running application but it can not be forced to quit, and I also can not restart my computer or shut it down. I simply have to use the power button to turn off the computer. I am using Nvidia GPU, but still having such issues. My system is OS X 10.2.2 Using Core i7, 16GB ram and 750M.
Houdini version is 14.0.258

twod
Upgrading to 10.10.2 helps tremendously. Apple's graphics driver updates are tied to their OS updates, unfortunately.

Ok, was putting this off but maybe now I have incentive!