Short bio: Computer Scientist, FOSS supporter (read more)
Tux Machines (TM)-specific
Enterprise users were never really fans of Mozilla's insanely rapid release cycle for the open source Firefox web browser. So, in order to help out enterprise users, Mozilla launched the ESR (Enterprise Supported Release) with Firefox 10. That ESR is still maintained with security updates as Mozilla updates the mainline branch currently at Firefox 15.
Mozilla developer Alex Keybl has now detailed the plans for how Firefox ESR 10 users will migrate (or not) to the next ESR release. The plan is for the next ESR to be based on Firefox 17 which should be out around November 20th.
Existing ESR 10 users will then have until February 19th of 2013 when the Firefox 19 release is out to upgrade voluntarily.