Everyone seems to be missing the picture. 100% on Demand, all the time, is what we're shooting for here. DVR-- okay, but that's just the stepping stone for On Demand All the Time.
I canceled my Comcast (er, Xfinity??) subscription 7 months ago and have not looked back. In fact, I watch more "TV" than ever through my Roku box, simply because I have many more choices at my fingertips 24/7. Not to mention that I'm paying 50% of the price (yes, including my bandwidth costs).
Of note is that I have an 11-year-old daughter, whose initial groans about ditching cable tv have been replaced by the complete delight she experiences discovering that her favorite movies and tv shows are already available on Netflix; and she is also discovering classic TV such as the Adams family and Ren & Stimpy and lots of other great stuff.
With this Hulu offering (which will only get better over time), the existing "gaps" in programming will become completely irrelevant (although they are already irrelevant to me personally). Not to mention Pandora Radio, which is available free through the Roku, out of the box.
PLUS-- I have a little USB ATSC tuner with DVR software, which records my network shows off of the air in full HD including Dolby 5.1 soundtrack. Remember that digital switchover? It worked! And the picture is way better than what my Comcast picture was.
Currently, this costs me 75 USD/month, which includes a kick-ass 4G internet service with unlimited bandwidth usage, VOIP, Netflix, and now Hulu. Considering that I was paying twice that much with Comcast, without any pay channels nor HD (which I'm not even sure why they were trying to charge me extra for) nor DVR, I'm more than satisfied.
Just thought I'd weigh in with my experience. I'm not a typical TV-addicted American; or, I didn't used to be.