Firefox 10 is due out later today. This is a significant release for all platforms, due to the "add-ons are compatible by default, with some exceptions" change. Also worth noting is that Firefox 3.6 reaches its end-of-life today. Its replacement is called Firefox 10 ESR (short for Extended Support Release). Those of you still using PPC Macs cannot update, unfortunately. Here's how the ESR release train works: Firefox and Firefox ESR updates will be released in parallel. There will be 8 updates to each initial ESR release, fixing only critical and high-rated security issues as well as the most important bugs. New features will NOT be introduced in these updates. The ESR updates will occur every 6 weeks. A schedule may help clarify: Firefox 10 = Firefox 10 ESR Firefox 11 = Firefox 10.0.1 ESR Firefox 12 = Firefox 10.0.2 ESR Firefox 13 = Firefox 10.0.3 ESR Firefox 14 = Firefox 10.0.4 ESR Firefox 15 = Firefox 10.0.5 ESR Firefox 16 = Firefox 10.0.6 ESR Firefox 17 = Firefox 10.0.7 ESR and Firefox 17 ESR Firefox 18 = Firefox 10.0.8 ESR and Firefox 17.0.1 ESR Firefox 19 = Firefox 17.0.2 ESR Firefox 20 = Firefox 17.0.3 ESR ... this pattern continues, with a new update every 6 weeks.