There's similar quotes in an interview with Larry and Sergey in "Designing Interactions" by Bill Moggridge. Sergey explains (in a lot more detail than I do here) that they kept the front page simple because they didn't want to spend too much time on the front page. Only afterwards did they realise how powerful that was, and they decided to keep things off there as much as possible.
The formula by Sivers he refers too seems to be the best approximation to value idea. I still like to put emphasis on execution instead of idea, since almost everybody I talk with that value idea is in fact doing some analysis paralysis and will start working when they get that "great idea".
This subject was presented in a book I read recently, along with many interesting aspect of how our mind works. The book is definitely worth reading, it was "Thinking, Fast and Slow" by Daniel Kahneman.
I wonder if it can explain the fact that I don't fall or bump into obstacles when I walk and read at the same time...
The fact that the majority of camera is privately owned is not relevant. The question remains: "Is 500 cameras too many, too little or just about right, for a county of 1 million?". I have no idea, but I don't see why the ratio public/private is important.
The article cited never asked "Is 12,000 ...". They say "Look cameras are not that bad since most are on premise and are privately owned and operated." I find that this comparison is dishonest and is not relevant.
edit: changed "you cite" to "cited", The response is not to the OP.
I used it while abroad. Since the GPS works, you can see where you are on the map, which is a big plus over only a paper map. Obviously getting data access would be even better, but it's a nice free alternative.