Stumbled across these draft chapters “Agile Estimating and Planning“ due to come out in early 2005. I've read most of the chapters and there is some pretty good stuff in there. I'll be ordering it when it comes out. It reinforces my belief that estimating is a skill, it needs to be practice and it needs a feedback loop in order to become good at it. It may sound obvious, but I haven't seen a lot of companies that do those things.