FF3 beta 5 has been out for a couple of weeks and its all good.

Point of note: Fedora 9, due for release at the end of this month, will include FF3
http://fedoraproject.org/wiki/Releases/9/FeatureList

The Fedora wiki did have a specific reference to FF3 beta 5 being the version included in the latest Fedora Beta at the time of code freeze, however it now says FF3 which hopefully means that the FF3 coders are done and have moved onto packaging for delivery.

The FF3 project status page confirms it:

Project Status

Most current activity on the Firefox 3 front is wrapped up in planning, scoping, and assigning tasks. Please see the features list and the planning documents linked therein for more information.
Roll up! Roll up!