Today we shipped Firefox 4.0 beta10. Lots of cool features in there, details already covered here.

We hope you like this latest beta. No doubt you’ve noticed its only been 11 days since 4.0beta9. We’re picking up the cadence as we get closer to the final release, doing betas more and more frequently, each with lots of improvements. Of course, please file bugs if you hit any problems!

Meanwhile, there’s one behind-the-scene detail that I’m most proud of with beta10.

RelEng got the “go to build” for each of Firefox3.5.17, Firefox3.6.14 and Firefox4.0beta10 all within 50mins of each other, all on Friday afternoon. We were able to generate all three releases concurrently, and hand builds over to QA Friday afternoon / Monday morning without any incident.

This is a great testimonial on how our release infrastructure has improved with the move to buildbot 0.8.x as well as the last 3 months of refactoring and general bug fixing. Of course, there are still lots more improvements we need to do – the next big step is underway, moving all the Fennec release automation code to buildbot 0.8.x and consolidating it with the Firefox release automation code. This will enable us to do multiple Fennec releases at the same time as multiple Firefox releases – something we feel is strategically really important for Mozilla in 2011.

Meanwhile, it was really great to see this infrastructure coming together, and how work done by RelEng so far has made handling those three emails on Friday feasible.