Well, I've got about 30,000 mi on mine, and I kept a log for the first 10,000 or so, and I was averaging well over 50 mpg, driving in a city and pushing the thing over 90 on occasion.
So I watched your video in the other thread. My observations:
When I lived in London, I'm pretty sure the guy who was hosting the show (the tall dude) was in the tabloid papers a lot... and one of the things I remember is that in addition to being a douche, he had Tory sympathies. So, sort of like posting a video of Dick Cheney maligning the Prius.
In any case, the reasons I converted my Prius to plug-in (probably very inefficient production process for the batteries if you add it all up) are twofold. Regardless of all the cute little videos, the thing (hybrid ownership) is moving away from OPEC dependency. With the plug-in, I am averaging around 80-90 mpg if I drive it less than 40 mi per day. Take that OPEC!
Secondly, although the production process is inefficient, as more and more cars like this are made, there will be economies of scale. The tall douche was mostly talking about economies of scale with his "nickel" diatribe... all Prius owners are probably aware of the inefficiency because the car is relatively expensive.
