I noticed the incident which precipitated this concern. The female creator of a harmless blog on web-design was subject to the most repellent online abuse, rape and murder threats etc. (I read some of the abuse, it was shit). She had a fairly high techy profile and used this - most understandably - to blow the whistle on her persecutors. The consequence is this call for some kind of self-regulation by bloggers.
I think some people act like arses under online anonymity, and the most offensive stuff I have read is by sexually inadequate (I assume) men picking on women who are perceived to be 'attractive'. I think it's awful and I am all for name and shame, ban and delete such comments.
On the other hand I think the idea of a blog-wide code of conduct, voluntary or somehow enforced, is ridiculous. Livejournal can have one, and enforce it, but blogs generically can't.
ETA Precipitating incident (report by the blogger herself)