One of the most frequent requests for Tapestry is support for global message catalogs. In Tapestry, each page and each component can have its own message catalog and that's good ... but this can also foster some duplication between templates. This is now fixed as TAPESTRY-242.
I think of all the changes I've made in Tapestry 3.1 so far, this may be the first one that came as a request from the community, rather than a change I've made from my personal vision for 3.1. Now that the basic infrastructure of 3.1 is in place (but subject to some revision and refactoring) I believe we'll be seeing these kind of changes rolling out quite frequently.