Although Google still hasn't shared many details concerning how much money YouTube is or isn't raking in, there's good reason to believe the site's doing just fine. A relatively high-ranking Googler indicated in an interview that the number of entities using display ads is up by about 1,000 percent on a year-over-year basis.
This notion comes from Barry Salzman, Head of Media and Platforms, Americas at Google, and there's not much room for misinterpretation. Salzman spoke to Brian Womack, and Womack was able to report afterward that Google "boosted the number of advertisers using display ads on its YouTube video site 10-fold in the past year."
That's a pretty impressive growth rate. Indeed, it sounds possible that YouTube's attracted more advertisers than it can handle (at least without plastering ads all over the place), which would mean that Google may be able to charge whatever it likes for display ads.
That state of affairs would obviously be beneficial for Google and its investors. Plus, if Google's turning away companies, it would help ensure that YouTube users are only exposed to the most relevant, interesting ads.
So perhaps YouTube's struck a good balance between making money and not annoying users. We'll be sure to inspect Google's next earnings report for more evidence on this front.