Not saying you should get rep for editing other people's posts but allow for some mechanism to encourage people to clean up questions (and answers if needed)
Some ideas to start the discussion:
- Edit counter on your profile page (and being able to sort users by edit counts)
- Being able to vote up edits (and have a separate edit reputation from your regular rep)
- More badges for editing
I think it's good for the Stack Overflow system as a whole not to be dependent on a few active editors. Since what happens if they go away or refuse to edit for some reason.