That sounds like it's crashing when you quit. No, that is not a common problem.
Did you install all the updates?
And we know of 2 crash on quit problems: one due to an OS bug, and one due to some third party plugins with bugs.
I just changed Operating systems yesterday going from OS 10.6.8 to 10.8 and the problem still exists.
Haven't disabled all the plugins and turned them on one by one yet tho.
Did you install all the Photoshop updates?
And if you have third party plugins, try disabling all of them to see if they might be the cause.
Then if they are, check for updates from the manufacturers.
I had the Adobe app check for updates to my CS5 but there weren't any more to be had. I'll have to check my pliugins next as you suggest.