There is a single post at WebmasterWorld where a senior member is complaining that Bing has reduced the number of pages they have indexed of his site.
He said he had about 500,000 URLs URLs indexed and now he only has about 350,000 URLs indexed at Bing. This occurred around May 5th.
So I checked several of my sites at Bing Webmaster Tools and didn't notice a change in the index rate at all for any of my sites. In fact, here is a screen shot of the index rate for this site, as you can see, there was a little increase one day on May 3rd or so.
But when I looked at my traffic, impressions and clicks, there was a huge change - for the better - on May 7th or 8th:
I also noticed fluctuations in the crawl rate chart, but that seems normal - to be all over the place:
Have you noticed any significant changes at Bing recently?
I am thinking maybe the increase I am seeing is related to the Bing social integration or maybe not?
The last possible Bing update was in late March 2012 according to my records.
Forum discussion at WebmasterWorld.