Why hasn't anyone at Google thought of introducing a ranking of sites on the lines of the services provided by Quantcast or Alexa. Considering the huge base of their Google Analytics subscribers, they would have a clear advantage.
A vast number of web sites (probably the majority) do NOT use GA. None of mine, for example, and some of those sites are popular for their niches and get good SERPS even with panda (though I'm not betting that will continue!).
Quite apart from that, a lot of people (myself included) turn off GA in web browsers. I will not have anything google anywhere if I can avoid it.
A vast number of web sites (probably the majority) do NOT use GA.
That's true but it hasn't stopped Quantcast and Alexa from putting out (estimated) numbers. Considering that Google accounts for a considerable portion of the traffic of most websites, knowing how much traffic they send a website should be enough for them to provide a reasonable estimate of the site's total traffic. This will not apply always but broadly speaking, it's enough to start a ranking system. I also think this will motivate webmasters to start adding GA to their sites. For one of my (quantified) sites Quantcast under reports traffic by half. Their estimates for sites not 'quantitied' are way off the mark. I believe Google will be far more accurate.
It's a great way of getting an idea of what the traffic quality is like at certain sites, regardless of PageRank. I prefer traffic metrics from sites like Quantcast and Google Trends for Websites over Toolbar PageRank. If the site doesn't register a blip on Google Trends then that is a sign that it may be useless for advertising purposes.
I meant a ranking system where we can rank all the sites..1st..545th..12356th etc...like Quantcast but more accurate. Google Trends while a useful service in some ways doesn't do that. There are just vague graphs.
Is the Google Trends data for your site accurate in terms of traffic numbers?