I love del.icio.us and use it quite a bit. One of my favorite utilities is the ability to tag content for others using the for:___ tag.
The ¨for:¨ tag, too, has turned into a spam channel.
The user jwp, at the URL http://del.icio.us/jwp has tagged a poker website with a for: tag for me, along with a lot of other people. That sucks.
I hope del.icio.us is thinking about this problem, too. I think it has the potential of pissing many users off.