After a fairly long struggle with Forrest, I've finally been able to get the Tapestry 3.1 documentation built properly. The upgrade from Forrest 0.5 to 0.6 has been very painful and, in fact, getting the documentation to build correctly requires the very, very latest from Forrest's SVN repository (what will become Forrest 0.7).
The results are pretty though (they're in a temporary location while the details get filled out, especially the new component reference).
In other news, parameter directions are dead. This is huge news if you use Tapestry 3.0 today ... understanding parameter directions was a real pain. Basically, you had to give Tapestry hints about how to synchronize the properties of your component against the properties of the page, effectively saying "I only access this parameter when rendering" vs. "I might access this parameter at any time." (vs. "Just let me deal with this in lots of Java code, please!").
That's completely gone in Tapestry 3.1. The new accessor methods for component parameter properties are now super-smart: they do what the old direction auto did, but handle optional parameters, type conversion, and really smart data caching. Less is more!