Sorry David, but I have to call you out on this one. Yesterday, you wrote a long post about how you won't use Tapestry b/c you have bills to pay.
Do I use Tapestry? Heck no. I have a mortgage to pay. Besides, I'm so comfortable with JSF that I don't know if it'd be worth the investment for me to switch to Tapestry. Also, JSF already enjoys more industry support and that gap will widen considerably over the next couple years as Tapestry maintains a small but rabid group of followers in a niche market, whereas JSF will dethrone Struts as the reigning king of Java-based WAFs. JSF will eventually have support for HTML views and custom components devoid of Java code, in addition to many other cool features such as built-in AJAX support and client-side validation.
Today we find that you're writing a book on Rails. So rather than spending the time to learn Tapestry b/c it doesn't pay the bills - you're going to learn Rails? What makes you think it will pay the bills better than Tapestry? Is Shale still the next big thing for you - or do you just like writing books?