Sitemaps are an important tool for search engine optimization professionals in that they provide an opportunity to expose or reveal to search engines the pages on their sites that they want indexed and crawled.
While most search engines do a fine job crawling pages on their own and don't always need the information that sitemaps offer, they are good to have as they provide webmasters a way to ensure that pages are at least available to the engines - and for many that's a really big deal.
Last week Bing announced the official release of its Bing XML Sitemap Plugin 1.0 which was initially released in beta back in February 2013. The open source server-side technology takes care of generating XML Sitemaps compliant with sitemaps.org for websites running on Internet Information Services (IIS) for Windows® Server as well as Apache HTTP Server.
Bing's plugin essentially creates two types of sitemaps - a comprehensive version (based on recent traffic activity - more on that shortly) which includes all the URLs on a site and a delta sitemap which includes those pages which were recently changed within a configurable time window (which search engines can then prioritize). Bing's plugin automatically adds the <lastmod> value and generates <priority> values based on how popular the URLs were (visit count - essentially, the priority of a page is calculated as the visit count for the URL divided by 2 times the average visit count for the entire host site).
The newly updated plugin has a number of other improvements and features worthy of note, including being able to automatically ping the search engines after each Sitemap update (only Bing and Google at the present time), a better computation algorithm of the <priority> value, configurable URL parameter handling, 404 handling, link rel=canonical handling, and flexibility of what gets added to robots.txt.
The Bing XML Sitemap Plugin (1.0) is available for IIS 6.0 or higher and Apache. The plugin binaries and source code is avaiable within the Microsoft Download Center or the Bing XML Sitemap download page in Bing Webmaster Help Center.