It all seems to work really well, but here's the rub: I haven't bought anything. The shows on there are just too expensive. One of the most egregious example I've found is Jimmy Neutron season one (can you tell I have kids?). They charge $1.99 for a 30 minute episode. That's $4/hour, or about the same as a first run movie at the theater! For further comparison, the "best of season one" DVD is $27 for 17 episodes, one of which is double length. So 9 hours of "entertainment" for $27, or $3/hour. Why would I pay 33% more for on demand, which I can't watch in my car, on a plane, or during a vacation. I can even get the DVD two days for free later thanks to Amazon on demand. Not even my six year old thought Jimmy Neutron was worth $4/hour.
There is a similar oddity if you compare HD shows to DVD purchases. They tend to cost more than the DVD (though the on demand for standard def costs less than the DVD). Given that it's not real HD (due to the reduced bitstream and bandwidth) it's hardly a compelling purchase. So much for Amazon on demand.
Don't get me started on the pricing for current episodes compared to Hulu.