No. Not in the sense that there is some mythical force making sure everyone "gets what is coming towards them.
I think karma is just some way we can explain a natural occurrence: If you are a dick, people will treat you like one.
Look at Liz. She is extremely nice, and loved here on MFK. When she was upset a while back, Oddball unslung the banhammer to get back at whoever made her upset. It wasn't because of Karma, it was because we love her.
Likewise, if we have a member here who no-one likes, and is being harassed, action would be taken, but not nearly to the extent shown above.
Just my .02