So, a couple of weeks ago there was this announcement that Yahoo! had purchased del.icio.us
I use delicious for my categorization needs. It works (worked) fine. That is, until it was purchased by the yahoos at Yahoo!
It's down right now, at least as far as I can tell. This is the second time in three weeks. I don't recall experiencing any downtime before the announcement.
I'm sure this will be spun as a new "feature" of the service, as they say in Billdom.