In their infinite wisdom, they changed all user profiles to BLANK! No warning, no automated way to get data back, and other unwanted changes.
The blog has such choice quotes as "We know this has been a rough transition for some of you and, and are committed to helping you use, understand, and (hopefully) enjoy your new profile." and "We also know lots of you worked hard on your old profiles and want your data. If you feel like you're missing data, we've saved a copy of your old profile (and alias) and our Customer Care team can retrieve this information. You won't, however, be able to revert back to your old profile format, but you will be able to get any data that you think is missing. To do this, please go here http://help.yahoo.com/l/us/yahoo/profiles/general.html to contact Customer Care."
There were 850 comments posted, all negative, on the first day. There are hundreds more today.
There is even more outrage on yahoo messenger blog. http://www.ymessengerblog.com/blog/2008/10/17/changes-to-your-yahoo-profile/"