Beta Releases
Mozilla did itself no favours with so many betas. From the users point of view it was a bad experience. Eg. he Hotmail debacle - okay it wasn't Mozilla's fault - drive me to try Opera, when I have been loyal to FF for years.
FF has become slower and slower over the years. Perhaps they should fragment the browser market - have a slower app for devs and heavyweight use, and a faster, lighter app for "browsing".