This comment on my previous blog post from John Walicki is so important, everyone needs to see it.
I have 500,000 corporate users on Firefox 3.6. We just completing a test cycle of Firefox 4 on many thousands of internal business web applications. Many hundreds of application owners and their test teams have participated. We gave them several months to ready themselves. We worked with dozens of internal Add-On developers and product teams to prepare their add-ons for Firefox 4. We’re poised to deploy Firefox 4.01 in 3Q when the corporate change freeze lifts. Education programs, documentation updates, communications all are planned. While several of us keep up with Aurora, I can’t expect thousands of app owners to do the same. I applaud the effort to accelerate the pace of Web experience and I expect to chase version releases well into the future. The Firefox 4 EOL is a kick in the stomach. I’m now in the terrible position of choosing to deploy a Firefox 4 release with potentially unpatched vulnerabilities, reset the test cycle for thousands of internal apps to validate Firefox 5 or stay on a patched Firefox 3.6.x. By the time I validate Firefox 5, what guarantee would I have that Firefox 5 won’t go EOL when Firefox 6 is released?
Are you starting to get the picture? And if that didn't make it clear, here's someone else from another very large company (>150,000 employees) that deploys Firefox:
I’ve been wearing the same corporate hat all day and beating my head on the desk. For most corporations, the technology is a tool for accomplishing their core competency and the business drives the technology. Being faced with deciding which is more important: security updates or the critical production web application needed to manufacture your product is not a happy place to be. A more stable release is needed when you are looking at large corporations with millions of pages of web content (sites, applications, etc.)
While the rapid release process sounds great, it's an absolute fail for large deployments of Firefox.