Interesting move, having worked a lot with Google Adsense and YouTube ad campaigns, I can tell you that theirs a lot of friction involved in the system that could be solved with Bitcoin.

Not having to wait for thresholds, not requiring a bank account, not needing to clear forex payments where they nail you with the conversion fees will be great for creators both in the US and especially outside the US

As for advertisers, as long as theirs no a lot of click fraud, being able to move your spend in and out of a system would also be appealing