The Bing bot is one of the worst bots there is. It's generating 1/3 of all traffic to my site (3000 hits over 24 hours), more than twice as much as the Google bot (1300 hits), though I've set the crawl rate for Bing enormously slow (In the webmaster tools as well in the robots.txt). It seems that the crawl delay is respected by each separate Bing server, but not as a whole. So Bing bot no. 1 could come every n seconds, but in the meantime Bing bot no. 2 comes along, then bot no. 3 etc.
What I've noticed is that Bing is not only using my sitemap (set up with OSMap), but it also tries to use any rss feed it encounters as a sitemap. When I look at the sitemaps in the Bing webmaster tools, url's with ?format=feed show up. If I remove these, they will appear again within days. And thus Bing seems to crawl more pages than needed.
I've setup Bing webmaster tools to ignore url parameters like 'format', but it doesn't seem te respect my preferences. I've also added a line to my robots.txt, but even that is ignored too:
Has anyone an idea how to tame the Bing bot? I'm not paying my hosting provider to please Bing, especially since it only accounts for less than 1% of the referral traffic.