A few of our users have recently complained that when upgrading to Firefox 2.0, the outbrain extension stopped working. Looks like we had a small glitch with the updating of the extension which affected some of our users, and it is now fixed.
To upgrade to the fixed version, go to Tools > Add-ons > Extensions, and click the 'Find Updates' button, Firefox should now find the most up-to-date outbrain extension which is fully compatible with Firefox 2.0+
If this doesn't work for you, simply click on the following link (in Firefox...), and you'll be prompted to upgrade to the latest & greatest:
http://dsf.outbrain.com/getoutbrain/dist/outbrainvote.xpi
For those who bumped into this - apologies for the inconvenience...