In his post Thanks Bloglines Mike Torres writes

Over the course of the last few days, we noticed a problem in the way Bloglines was displaying feeds from MSN Spaces.  This problem was due to our recent URL change and the way we're redirecting visitors from http://spaces.msn.com/members/mike (as an example) to http://spaces.msn.com/mike.  Instead of providing the absolute URL to the RSS feed when Bloglines and others requested the feed, we're only returning the relative URL (i.e. "/mike").
 
Because of this, Bloglines had to turn around a fix to support relative URL redirects in record time.  Within just a couple of hours of contacting them, they had diagnosed the issue, fixed up all the Spaces feeds in their entire system, and patched the redirect logic to make sure it wouldn't happen again.  During this time, the subscriber lists/counts associated with a feed weren't updated for a little while (my 362 subscribers showed as 9, but my ego wasn't bruised) and they even did the extra work to merge "new" feeds with "old" feeds (because when the feed broke, and someone subscribed to the correct feed, Bloglines then had two records for the 'same' feed).
 
In short, this was truly great work by Mark Fletcher and the Bloglines staff.  Sorry guys for keeping you up so late on a Tuesday night!  We'll be making a change to the way we redirect shortly just to make sure this won't be a problem for anyone else in the future.  And for you Bloglines users, you should be back to normal for any MSN Spaces feeds in your list!

Mike and I exchanged mail with Mark Fletcher about this issue on Tuesday, and as he writes we were both grateful and impressed at how quickly the Bloglines folks made changes to fix the consequences of a bug in how we were sending HTTP redirects. Mad props to Mark Fletcher and the folks at Bloglines. You guys definitely rock.