Search engines (like Live Search, or Google) work by “crawling” the web, looking for web pages and reporting back on their content. Live Search has been making improvements on the crawler, and will be testing a new improved crawler in the coming weeks. According to Jeremiah Andrick over at the Live Search Webmaster blog:
In the coming weeks, we will be testing an update to MSNBot, which may show up as a new crawler name in your referrer logs. The new crawler user agent string will appear as:
You’ll still see the current version msnbot/1.1 (+http://search.msn.com/msnbot.htm) as Live Search’s primary user agent. We intend to ensure that any robots exclusion protocol you are using is respected. As such, you don’t need to update your Robots.txt file. We plan on crawling at a slow speed during the tests with the updated version.
Live Search added new functionality to the MSNBot/1.1 earlier this year, adding support for HTTP Compression and Conditional Get. Improvements to the search crawler don’t quite rank up there with news about a name change, an acquisition of Yahoo Search, or hiring a new boss, but in the long run could be as significant, if it improves search relevancy.