Almost all bits required for the firefox 3/xulrunner 1.9 rc1 transition are now available for pre-testing in the mozillateam ppa.
If you end up without your preferred translation you might also want to grab your langpacks from the ubuntu langpack ppa.
Next steps are: (hopefully tomorrow) push all bits to hardy-proposed; do thorough QA for about a week and finally release everything to hardy-updates.
Have fun!