Safari as the fastest browser will be beaten by Firefox in the near future. Mozilla has announced that they already released Beta 5 version of Firefox 3.
Firefox 3 is based on the Gecko 1.9 Web rendering platform, which has been under development for the past 32 months. Building on the previous release, Gecko 1.9 has more than 12,000 updates including some major re-architecting to provide improved performance, stability, rendering correctness, and code simplification and sustainability. Firefox 3 has been built on top of this new platform resulting in a more secure, easier to use, more personal product with a lot more under the hood to offer website and Firefox add-on developers.

Firefox 3 Beta 5 includes more than 750 changes from the previous beta, improving stability and web compatibility, providing platform and user interface enhancements, and resulting in the fastest Firefox ever. Many of these improvements were based on community feedback from the previous beta.

What’s New in Beta 5?

Integration

Personalization

Performance

You can find out more about all of these features in the "What’s New" section of the Mozilla Firefox 3 Release Notes. Testers can download Firefox 3 Beta 5 builds for Windows, Mac OS X and Linux in over 30 different languages.

Note: The Firefox 3 Beta 5 milestone release is not recommended to download for anyone other than developers and testers. It is intended for testing purposes only.

You can download Mozilla Firefox here:
Mozilla Firefox 3 Beta 5: Try Firefox 3 Beta 5.