A beta version of Moodle 1.7 is now available for wider testing! The Beta status means that it's reasonably stable with no critical bugs (that we haven't found in the past few weeks of heavy testing and fixing). DO NOT use it on a production server yet. If you are upgrading we recommend testing on a COPY of your Moodle 1.6 database.
If you would like to help us polish this release into a final release, please see the Testing and QA forum for discussion and instructions, or simply start using it and filing bugs on the Moodle Tracker.
Please see the Moodle 1.7 release notes for full details about the features in this release, and as usual, you can download it from the Moodle download page.