Bots
According to Yahoo! blog they have their new bot (Yahoo! Slurp) version in action that will reduce the number of requests and bandwidth consuption to crawled sites.
Almost at same time MSN renamed few its bots (they were named the same before) to help better distinguish them apart. So from now:
The MSN Shopping bot – msnbot-products
The MSN News bot – msnbot-news
The MSN Search bot – msnbot
The MSN Image Search bot – msnbot-media
This will help you better understand what is MSN doing on your site 😉