wilderness - 12:22 am on Feb 12, 2013 (gmt 0)
It's all the same robot from the same place, right? They're not showing up from 479 different bing/msn IPs in succession.
Their all using the UA msnbot-media/1.1.
As to IP, their all MSN IP's, however they are certainly NOT the same.
No request for pages with msnbot-media/1.1 UA, all requests are for robots.txt alone.
BTW the requests in the latest 24-hour period slowed down from the previous high, to 250.