Firefox Product Director Mike Beltzner gave a presentation yesterday about Mozilla's vision for Firefox 4, the next major revision of the open-source browser. The three pillars of the big plan are standards support, full user control, and "super-duper fast" speeds.

As Beltzner writes, it's usually not the case that plans for a major software release are put out in the open this early in the process, but Mozilla's open-source nature and development model are a bit different. You can watch Beltzner's presentation and discussion on the plans here, if you're using a browser that can play HTML5 videos in Ogg format (Firefox, Chrome, and Opera, mostly). Otherwise, you can peek at the slides explaining how Firefox aims to be fast, customizable, and adaptive—and why parts of Firefox 3.7 turned into the 3.6 branch, and the rest was saved for 4.0:

We've all had a peek at some of the new components in 4.0, including built-in contacts, no-restart-needed Jetpack extensions, and the new look. Beltzner's slides (viewed in full) offer more detail on what's coming, what it all looks like, and why it's important.
Firefox 4 Aims to Be "Fast, Powerful, and Empowering" - Firefox 4 - Lifehacker

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Firefox 4: the HTML5 parser – inline SVG, speed and more ✩ Mozilla Hacks – the Web developer blog