How Many People Skip Ads With Their DVRs?

This post refers to

Dennis O’Brien:

The vast majority of television content – even that on YouTube and Hulu – relies on ad dollars. Broadcast of course, is in the unenviable position of being totally dependent. In the short term, ad skipping tightens the noose on the traditional broadcasters especially, which generate almost all of their cash in ad dollars. Less money for them means cheaper programming – hello even more reality TV! The question is, if these ad dollars go away, or erode further, where will the money to produce these shows come from?

This model seems so broken to me already. I know that they have no way to tell exactly how many people fast forward through commercials when watching DVR’d programs, but I would wager that it’s most. So this just makes it easier. How effective are TV ads? Isn’t this model in need of re-vamping anyway?