I'm quite certain that this thread is covering a few stability issues associated with Mavericks.
My problem is not a hard freeze, as I still have control of my mouse, but no input events are registered from the keyboard, mouse or power button (sleep). Something definitely blocks IO, it's just strange the the mouse movement still works. For those experiencing this problem, I highly recommend running the flash uninstaller from Adobe and see how things go. So far that appears to have solved my problem. I'm guessing apple will have a fix for this eventually if it is indeed the problem.
Others that are getting hard lockups should go to the apple store as they will need to check the crash logs. I had one crash already that was related to the suspend/sleep functionality. You may be able to disable that in the short term to see if it solves the problem. Obviously that's not an acceptable long term solution, so it's best to get your crash logs to apple so they can properly diagnose the problem.
I understand the concern from many that they are disappointed that Apple has these types of issues, but to be honest, this is par for the course for apple as far as mac os updates go. It's usually better to have us early adopters go through this, then upgrade when a few patches have been released. Once solved, the system is generally far more stable than the windows equivalent.