How Important is Alexa Ranking?

Alexa tracks a website's traffic history, and gives a ranking based upon the number of visitors using Alexa toolbar. We all know that Alexa ranking lacks in accuracy, but Alexa rank is important because:
There are lots of customers and advertisers who take Alexa rankings seriously, many “money maker program” still count this to determine how popular is our site. If you want to sell ad space of your website through services like Text-Link-Ads, you need a better Alexa Ranking and Google PR.
There are many online shoppers who are still very skeptical of where they’re going to shop on the internet. So they usually follow the others and use ratings like Alexa, Google pagerank or other traffic rankers to perceive the value of your site.
Too many people mistaken concentrating entirely on improving their Alexa ranking. Alexa numbers can be wildly misleading and manipulated. Since not every Internet user has the toolbar installed, Alexa will multiply the number of visitors by a specific margin to estimate the total number of visitors a site may typically get.
For instance: For every Alexa toolbar user that visits a page, Alexa may assume that another nine non-toolbar users visited the same page. For every 100 toolbar visitors, Alexa may estimate 900 non-toolbar users are also visiting the same page within the same 24-hour period.

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