Mozilla 1.8 alpha 6 released. Yes, Mozilla Organisation is still working on Mozilla, even under the extensive promotion of Firefox.
Mac OS X Disc Image
Linux Disc Image
Windows Installer
Windows Zipped File
Mozilla 1.8a6 Release Notes
Change Log
Mozilla 1.8 Alpha 6's release notes do not yet list what changes have occured to the software since the release of the last alpha in November, but a rough changelog is available containing over 400 entries.