My Mountain Lion won't recognize USB controller button presses... Why? All right.  I've played games on my MacBook Pro using a crappy Microsoft Sidewinder gamepad for years, plugged into my USB port.  I just upgraded to Mountain Lion a few days ago, though, and for some reason, I can't get any programs to recognize my controller's button presses.  System Information (not System Profiler anymore, I guess) will tell me it's plugged in, sure, but no programs will actually register button presses.  It's rather odd, and extremely frustrating since I would really like to, you know, use the controller.

I've tried unplugging it and plugging it back in after a few minutes.  Or hours.  I've tried restarting with the controller not plugged in.  I've tried restarting with the controller plugged in.  I've tried using a different controller to rule out controller malfunction.  I've tried using a different USB port.  (I have a USB mouse and it works in either port.)  I think signs point to a driver issue, but why would Mountain Lion suddenly be incompatible with my controller if it worked under Lion?  Something's very strange here.  Thank you very much!

EDIT: The USB Prober app from the Hardware I/O Tools download (from the dev site) sees my controller just fine.  It identifies it and everything.  Other applications, on the other hand, don't...

EDIT x2: I restarted with the controller in the port, and it was working!  Hoorah!  I used ControllerMate to see what was up, and it recognized everything I did!  I played a game with it and quit the application.  But now it no longer works; ControllerMate suggests that some other software is controlling my controller.  I've had issues with this with my built-in camera before, years ago, but they kinda just went away.  So I'm still stuck -- unless the only way is to restart every time I want to use my controller, which is kinda anti-Mac.  Suggestions?

EDIT x3: Well, that's kind of odd.  The Ink preference pane showed up for some reason.  And weirder, after a restart where my controller was connected during startup, I could use the controller as a mouse.  It was actually moving around the pointer, though only in an absolute sense: when I let go off the direction pad, the cursor jumped to the center.  I disconnected the controller and plugged it back in, and now it doesn't work again.

EDIT x4: The Ink prefpane was due to SteerMouse; I uninstalled it and the prefpane went away.  I also reset my NVRAM, but no change.  However, I figured out something very important.  I had the controller running, then I used Chrome for a while.  Controller was still running.  I used Chrome again.  Controller stopped.  Gah, not again.  I quit Chrome.  Controller came back online immediately.

SO THE PROBLEM IS CHROME.

Perhaps the reason I thought it was my Mountain Lion update is because Chrome did an auto-update at the same time, or perhaps Mountain Lion breaks Chrome's behavior, or perhaps Mountain Lion's USB drivers don't like Chrome.  Whatever the situation is, I've at least managed to pinpoint the problem better.  Still not solved, though...
I was having virtually the same problem and it turns out Chrome was the cause.

I'm using an Xbox 360 controller on Mountain Lion with the tattiebogle driver.  Recently, my controller would just cease to respond, even though it was showing as connected and no amount of disconnecting/re-connecting would fix the problem; the only thing that seemed to work was a re-boot.

I was doing some research earlier and came across this post.  I found it hard to believe that Chrome would be the cause, but sure enough, the controller has stopped working twice now and both times I closed down Chrome, re-connected, and all is fine again!  Thanks for your post, it helped me a lot!