I'm pushing for a way to easily disable signature advertising on a per user basis, it would be a setting in your profile you could set yourself. Either filter them by keywords or regex, disable special characters and formatting to make signatures less obnoxious, or something similar.

If one can disable forum ads, one should be able to disable sig ads as well. Since signature ads are so much more prolific it only makes sense. Shouldn't have to disable signatures entirely just because because of ads, users should have the choice. Signature advertising would still be possible, just less effective, and would cut down on the spam without so many users needing to be moderated.

It would also mean sig campaigns would need to be much more responsible. If your campaign has lots of spammers in it that you are not controlling, then people are going to block your ads.