The new tool for backlinks analysis is available at _http://ahrefs.com since march 2011.
It provides lots of useful backlinks statistics for your and your competitors' (or everyone else's) sites.
Distinguishing feature of this tool is an independent database refreshed in realtime (circa 6 billion external and 25 billion internal links added each day).
You're welcome to try new possibilities on any URLs you are interested in!

Here is a new great feature by Ahrefs.com! Ahrefs Top ordering the most significant internet-projects by their referring IP's quantity! Who is the first million of Internet by objective criteria of referring popularity? Monitor them at _http://ahrefs.com/ahrefs_top.php !

Here comes a new possibility of importing data from Site Explorer into the CSV and Excel formats. It allows saving data on your computer for further analysis.

For subscribed users there appeared a new type of report - Raw Export Report. It enables exporting up to 5 million links for any domains. Users with Starter Subscription may export 1 million links, those with Standard Subscription - 5 million links every month over a subscription period.

New free option is in the pipeline - trial usage of all paid services. You can build 3 standard reports for 500 links for any domain (not necessarily yours) for free, as well as to export 10000 links through rawexport. These limits are enough to analyse the efficiency of reports and export functioning. If you like the result you get and want more info, you may subscribe and get considerably higher limits.

We've been planning to launch API in the end of August, but already now we get many letters with API request and in connection with the fact that Yahoo Site Explorer API is going to be shut down, we've decided to launch version 0.1, which may be used right now.

Current API version enables:
1.to see links on the indicated domain, directory or URL
2.to see info about pages on a domain or in a directory

More advanced options will come, as promised, in August. To read more about API 0.1, follow this link - h ttp://ahrefs.com/api/

We've lowered prices for our API usage. Now its opportunities are easily widened according to your requests; our immense data amount makes it possible to offer different samplings on its base. If Yahoo Site Explorer shutting down is a problem for you, we advise you have a look at our service.

This looks like a pretty accurate system.

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New cool feature from Ahrefs: from now on it is possible to find out what keywords make any site site appear in Google, Bing or Yahoo SERPs - _http://ahrefs.com/serps/positions/

I compared it to some other tools and it's pretty dead on with the others. Thanks for this.