Who the hell needs 12 cores even if you are doing video processing? Surely 6 is more then enough unless this machine is going to be a server for many users?
Well, it depends on how much you do at once really. If you are doing some huge operation that's going to take awhile, and you have some free cores, then you can feel free to go do something else to increase your productivity. It's pretty sweet.
And then there's BOINC.