I think that for most people the right path to follow is the path that you took. If you turn the dissertation into a book without publishing any parts of it, it will be hard to get it into a top publisher and hard to get people to read it. Since you rarely need a book to get tenure, it seems like turning the dissertation into a book is a good way to waste some of your most valuable resources (i.e., time and raw material for future research). That being said, you might be able to get a few papers out and a book proposal in before a tenure decision is made or in order to move to a more attractive department prior to tenure. In my experience, trying to publish parts of my dissertation led me to improve upon old work and think about new topics to discuss in future research. If I had just put the dissertation out as a book (as if that would've been possible), the research would have been a bit stale and the writing of a book that much more tedious. I don't think it's the norm that people emerge from graduate school fully formed, so taking your time and publishing papers first strikes me as the sound policy for most young faculty members.
Converting a dissertation into a book means turning something people have to read into something they’ll want to read. Look at it as an opportunity to publicize (the original concept behind the word “to publish”) your project so that as many people as possible can learn from the years of work that you’ve done. Even before you start to revise, think hard about whom you’re writing for and how you can make your ideas accessible to as many people as possible. If your dissertation was written in academese and involved imbricated but epistemically free-floating signifiers, try to translate it into language that people outside of your field will understand.
From Dissertation to Book - The Chronicle of Higher Education
On May 11, 2012 Astrid Eich-Krohm and I participated in an ASA Professional Webinar about the Dissertation to Book Process. It may be run again this fall. In the meantime, here are the powerpoint slides from the ASA workshop, and a companion handout.