I don't know how to put a stop to this sort of invective blogging. You can read all about it at Forbes.com in an article titled "Attack of the Blogs" by Daniel Lyons.
I am concerned about how blogs may have a dire effect on the outcome of the next presidential election, but I don't think it can be helped. The only laws that I would consider tightening are slander/libel ones. I don't think that blogs or speech should be censored. People who lie should pay the price.