4 days now (since the 15th at least) and nothing out of YT. I realize that the portion of their viewers interested in MIT OCW or Blender is small, compared to the portion interested in FNAF and dental surgery on characters from Frozen... but it's also probably the portion they want to piss off least as an internet company.
The hope for many, perhaps a vain one, is that negatively impacting technical organizations (open source projects or MIT's ability to host computer science course videos) will have a disproportionate effect on the developers of youtube who on average might care about about these sort of organizations more than others. It could hurt youtube developer morale and/or their ability to recruit.
More basically, I only see their ads because there are non-ad videos that draw me to the site and give me a reasonable average impression of the combination of content and ads I see. Remove non-ad videos from YouTube and you would need to cut ads down by 50% to retain viewers like me.. the lower split of sharing on all content and/or lower viewer numbers will further dustress people with ads enabled on their content.. pushing them further into a death spiral of low profitability, poor content and inadequate incentives for the commercial content they apparently want.
ed: see below comment from OscarCunningham