Alexa

Alexa is pretty famous. Most people still use it although it might not be that accurate. Getting a good Alexa rating is important both for you to get advertisers and readers.

Technorati

Technorati is accurate, you need this if you want to be known by bloggers. If you can get in the top100 your site will be loaded with traffic but you need traffic to get there in the first place. Advertisers and bloggers take your technorati ranking into consideration for various reasons.

Pagerank

I guess most people know this one. Pagerank can be easily gained and sometimes is just full of crap. You can quickly get a pagerank but it can dissapear just as quick. Many places where you can write content for money takes Pagerank serious even though some of them dont even have pagerank themselves.

Compete

Compete is still fairly new compared to Pagerank and Alexa but this one is also a bit more accurate than Alexa. Although its not yet that widely used.

Blogcatalog

Blogcatalog has a ranking from 0 - 100. I think this works by how much traffic you get to your blog which is measured with the embed code if I am correct. This is great if you are a regular user and part of the community at blog catalog

Search engine position

Search engine position is a way to see how you rank for certain search words. Its also important and can get you loads of visitors if you can be positioned at the top for widely search keywords

Websitevaluecalculator

My site is worth $3,941.
How much is yours worth?

http://fromtheold.com/websitevaluecalculatorcom/

Realrank

What? This bunch of losers

Quantcast Rank

Sort of like Compete but just a bit different.

Google BackLinks

Google backlinks are the number of links you get from other sites to your site that actually shows in google backlinks.

Yahoo BackLinks

Same as above but just Yahoo’s version of this.

Live Search BackLinks

Also the same just Microsoft’s version.

Ask backlinks

Ask.com’s backlinks, works the same as Google backlinks

Feedburner

Feedburner matters for bloggers and advertisers as this shows them how much people are subscribed to the site. If you have a lot of subscribers you can display a button / widget showing the amount and some people subscribe to a site just because it has many visitors. So this helps for money and traffic.

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