I'm very pleased to announce the release of Yesod 0.4.0. This release includes new major versions for WAI, Hamlet, persistent and web-routes-quasi, pulling in a large number of new features. As an introduction to this release, I've begun a multi-part screencast of a blog tutorial.
Other major changes: include a large architectural overhaul of persistent, which does not affect user code very much, but gives much more flexibility in using the library; an updated parser for Hamlet allowing some nice features like quoted attributes; a more sane subsite syntax hopefully allowing interoperation with other frameworks; and much more.
I keep the changelogs separate by project, you can see each of them here:
Unlike other releases, I don't have any major features planned next, so I'm very interested in what the community has to say at this point. I'm hoping to get a few more WAI backends working soon (waiting on some feedback from Snap before releasing a Snap-powered handler), but otherwise I'm open to suggestions.