Yahoo’s new blog service called 360 , which till now was not open to the public is now up and open - you should be able to sign in using your yahoo id. You can do a lot of things in addition to the blog such as Photos, Reviews, Links, Blast (which is an online conversation thread - looks quite similar to a chat session), Radio, etc. Check out a sample page provided by Yahoo which shows their vision. I have been waiting for this to go live for a little while, and though Yahoo has come late to the game of blogging, it sure has added a lot of stuff which allows it to catch up.
You can check out my 360 page here .