I'm a bit baffled, I must confess, at the fury that has broken out here. On occasion, I have pointed out to people that they have forgotten to separate their tags with commas, resulting in a huge tag that will never, ever, match anything else in the universe. So a five word, fifty character limit on tags seems quite sensible to me. The message telling me about this had a huge list of long tags I had used, and to be honest, none of them were actually written for the main purpose a tag should have.
Which is...
In online computer systems terminology, a tag is a non-hierarchical keyword or term assigned to a piece of information (such as an internet bookmark, digital image, or computer file). This kind of metadata helps describe an item and allows it to be found again by browsing or searching. Tags are chosen informally and personally by the item's creator or by its viewer, depending on the system.
Thanks to Wikipedia.
In fact, I was only bothered at all by the loss of a couple of them, the one which said "09-f9-11-02-9d-74-e3-5b-d8-41-56-c5-63-56-88-c0" which has great sentimental value, and the one which said "Mind you don't step in the Griffin".
I can still find all the posts I have made about politicians eyes by searching on "eyes". So what remains is still a tag system, and the blog servers now hold considerably less inappropriate cruft. So probably searches will be a lot faster too, and that is good.
Update: see! They have noticed the fuss, and have an answer.