This is off the top of my head, but here are some of the highlights:
New Language system. This uses the same translation calls, but is being broken down to a more reasonable page load time. The initial work is complete, and seems to be working good.
Shared Tables for multiple sites. We are now using the prefix for the tables for something more than just a helpful way to move the Nuke tables out of the way. You can now define what prefix to use with what table, to allow you to share tables with other sites on your server. IE. If you run three PostNuke sites on your server and you want them all to share the FAQ, but nothing else, you can share just those tables.
Archived Submissions -- Don't want to delete a post, but don't want to publish it either? You can now archive the submission for later review.
New FAQ Features -- Include the ability of your users to post questions to the FAQ.
I know I am forgetting some of the features added, but this was meant to be a brief overview. There have been numerous improvements to the codebase in general, and we have spent the last few days doing nothing but bug fixing.
We hope to have the package together tomorrow sometime. Thanks to all that have helped, and all that have pointed out bugs!