A few more bits of info from Laura Thompson's presentation, that was mentioned: shipping features can be done even faster if they are done in a modular way, as addons. Firefox supports restartless addons, which means the browser could download an addon and enable it immediately.

Together with work on improving addon APIs (APIs for CSS features were discussed, for example) this could be very interesting.

If this means that I could easily uninstall all the bits of firefox I don't use, like bookmarks, that would be pretty cool.

Here's how I read it... they're looking at ways to move towards rolling release for A/B testing.

Think about it like this, you're using Firefox and you get a notification... "Feature X is ready to test, would you like to try it out? Yes/No" If you select Yes, the feature is rolled out to you and other volunteers immediately (potentially without restarting, depending on the feature), and you can then feedback your experience to Mozilla on how well the new feature works out for you. The feedback from this control group then informs whether Feature X is ready for prime time.

In some ways it seems like it's a restructuring of the Firefox development channels, a mix of beta and stable releases in the same channel.

This is kind of what we have in mind.

The model is that we want to make Firefox itself more webby in the way it ships. Features should be independently updatable from the core browser, and we should be able to do phased rollouts to help us watch for issues, control for load, and so on.

We are looking at offering very experimental stuff in a purely opt-in process, and updates to regular features as if they were third party add-ons (with some twists in how they have to be implemented).

It's mentioned only briefly here since the email is mostly about XUL/XBL.

I'm working on the Go Faster project. We hope to deliver a 1-2 features this way by the end of 2015. We have just started on building out needed changes to the client, update service, and build pipeline.