Relevance of Alexa rankings

How useful Alexa ranking is; has always been a subject of debate. It has always been argued against it that any tool that intends to deliver information only if installed on your machine, can not deliver accurate results. After all, per this method, if every thing else, including the algorithm employed by it is perfect, perfect information would require Alexa bar to be installed on all machines worldwide.

What exactly does a bar do and does it collect any of your personal information from your machine has also been a subject of debate. Alexa is a tool from Amazon Company and boasts of a good installed base on machines worldwide. Whether it conveys meaningful results or not fact is we webmasters have accorded it more respect to it than it might actually deserve. We end up valuing worth if a site, or worth of a link or price of a paid review based on various factors out of which one is Alexa ranking.
All said and done, Alexa does give a fair estimate of traffic ranking of a site in web market place. Now Alexa bar is usually installed on machines of webmasters or IT geeks. A common man, at least I have serious doubts, would ever have heard of Alexa ranking. So, it means sites not frequently visited by webmasters are prone to lag behind.
One argument that has given fresh ammunition to Alexa baiters is recent ranking where Alexa ranked YouTube higher than Google. It is argued that Alexa has become useless as a method for measuring web traffic and reach. Comscore tells a much different (and more accurate) story - Google is nearing 100 billion monthly page views; YouTube sees around 16 billion. They argue that for smaller sites it is understandable that Alexa may not have good data. But Google and YouTube are among the largest sites on the Internet. To get it this wrong is embarrassing.
I personally don’t agree with this and I think it is being unnecessarily been biased against Alexa. Basis of Alexa was ever universally accepted one, but to say some one else is better is fine till we detect another authentic instance of its wrong result.
No doubt Alexa is easy to manipulate but I think so is Google to some extent. There is a parallel industry that boasts of getting you good rank in Google results. Alexa never claims of delivering more than a a right ballpark estimate of traffic. It is at best better than nothing, and nothing was all we had when it came to free data until Alexa.
Advocates of Alexa also argue that it is not surprising that if YouTube.com DOES have more page views than Google.com. YouTube only had a .com site until very recently, when it rolled out 9 other TLDs in France, Spain, Brazil, Japan, etc. Google, however, has had more than a hundred country specific sites for a long time. And people use them. Germans go to Google.de, not Google.com. So, Alexa traffic for Google.com is only a fraction of worldwide traffic to Google.
Time has come, Pageview metrics is no more a reliable way to measure web traffic. Instead, the next reliable metrics in today’s AJAX era is the average time a user stays with the focus on your page (and browsers could implement this for each individual user).
Everybody knows that Alexa is not accurate. But this doesn’t mean it has no value. It is still the easiest way to have a first picture of a site’s traffic.