Twitter adds explanations to trends
Twitter seems to be adding an explanation to some trends, sourced from whatthetrend.com (apparently it did this last September, and I've only just noticed! Having said that, other people on Twitter haven't noticed either so maybe it is new ...). Here's an example for a search on John Terry today.

Explanations added to Twitter trends
Seems a good innovation to me. Should help with some of the more mysterious trends that only carry on as people ask why is X trending.
This is one of those things that I think is new, but feel free to correct me ... (See addition above. Not new at all!)
Yeah it's quite a useful thing really, although it has been around for months now I think. I barely use the Twitter website as I have TweetDeck as my main Twitter client, but do occasionally visit to see if there's been any changes of note.
I'm not sure how they decide which trends to provide descriptions for, as it doesn't seem to happen on all of them - even ones which seemingly last for days.
Yes, it does seem to have been around for a few months. But me and a few others on twitter have never noticed it! It definitely wasn't there on friday or saturday for john terry, making me wonder how quick it it (and therefore how useful it is ...)