I’ll add my voice for a vote on this as well. I’m currently moving an old pixelpost installation over to WP. There are over 2600 posts, each with only one image and nothing else. Just a photo. (It’s a photo a day thing.) While working on this, for every single post I am working on, it autosaves endlessly. Adding the lines to the config doesn’t work in the new 3.4. Yes, I ***WISH***WISH***WISH*** that we had the option to just SHUT IT OFF.
Clearing out the autosaves and post revisions has cleared more than have the space on my database.