From the Competition dept.:
Mozilla, faced with new competitive pressures, has begun work on three separate, significant changes to Firefox.

First is a new JavaScript engine that--with a transfusion from the project behind Apple's Safari--should run Web-based programs at least 30 percent faster. Second is a new graphics engine for Windows that will take advantage of hardware acceleration for graphics and text. And third is a programming tool to help bring to fruition a new system for Firefox add-ons.