Domain Score and Page Score are Microsoft search engine Bing's version of Google's Page Rank (PR). According to sources, the Domain Score and Page Score are based on the Bing ranking algorithm which analyzes factors such as domain age, quality of content and backlinks, and site popularity among others.

How to find your Bing DomainScore / PageScore at Webmaster Central
Bing Community member Quality Directory tells us how:
How to find your Bing DomainScore / PageScore at Webmaster Central
Bing Community member Quality Directory tells us how:
- Login to your Bing Webmaster Tools account, if you have one, and click on the "Web address" of any of your registered sites.
- Then you will see the "Domain Score" of your website and the "Page Score" of individual web pages.
- If you don't have an account, register at the following URL with a Windows Live ID: http://www.bing.com/webmaster/.
- After that add your sites and verify them by adding a given Meta tag to the head section of your site's homepage, or uploading an XML file to your server. Normally the site's data will populate within a couple of days after that.