Microsoft last week announced that it is going to unleash a new search engine bot within the next few months (currently scheduled for Oct. 1) called "Bingbot" http://www.lbi.co.uk/blog/bing-to-launch-bingbot/.
For many who use java script based web analytic tracking tools (i.e. Google Analytics, Omniture, Webtrends Ondemand, etc.) this new bot will go unnoticed and have no impact on your web analytics reports. However those out there who are using traditional server access logs (web logs) its time to prepare.
By now you should have a bot filter that removes most non-human (bot) traffic from your primary analytic reports. Don't wait until the new bot is out there to update your list update it now.
The new bots name is "msnbot/2.0b" and will replace the old "msnbot". Consider this an addition to your list. If Microsoft follows its old pattern of renaming bots or that the behavoir of other search engines, there will be at least a couple of days overlap where you site could be visited by both . This way your reports will remain unaffected when the new bot comes into play.