Evan Williams has posted Ten Rules for Web StartUps, and it seems to me to be a pretty brilliant piece. My next book is going to be about startups, and Evan will be one of the first people I interview. I particularly like his first rule about maintaining narrow focus.
In the 25 years that I've consulted startups, I found lack of focus to be the number one cause of death, more than lack of financing, more than technology not working as it should.
Nice job, Evan.