The third beta was set to be released in January, with the full version to follow shortly thereafter. The third beta, you may also remember, was not in the original plan — developers decided to add it in last November to allow them to work out some final kinks.
Now, it seems those kinks may be greater than initially believed. Mozilla’s meeting notes from this week indicate 18 bugs still require fixing from the second beta before Firefox 3.1 Beta 3 will be ready for release. The notes say the team doesn’t even yet “have a good estimate for when [it’ll] be done,” explaining that “many of the bugs are proving to be tricky and complicated to fully resolve.”
Though Firefox developers call the bugs “quite containable,” they now say they could conceivably push back the final Firefox 3.1 release past the first quarter of the year.