To be honest I wasn't even aware that eBay had switched the feedback history, but upon reading your post I decided to check my own feedback history to see whether or not I could see a description of anything that I'd purchased (or sold) over a year ago. With the exception of items that I've purchased which were listed by the seller as private listings, there is a description against all of the items that I've bought or sold on eBay since I opened my account.
With regards to your own listings, having looked at your own feedback I can only see a handful of purchases that state what the item was. The vast majority are not displaying any information that would make it clear as to what item you purchased. Therefore, I would say that this is either just a temporary glitch, or if not then perhaps eBay have been trying to set the feedback history up in such a way that each user can view a description of all items bought or sold since they opened their account, but something has gone wrong and it is now possible to some extent to see what other users have bought and sold as well.
