I downloaded the latest beta, Firefox 3.5 beta 4, to find out for myself. I used it on two different PCs. The first was my workhouse Windows XP SP3 system, and the other was my Fedora 10 computer. The XP box was a Dell Inspiron 530S with a 2.2-GHz Intel Pentium E2200 dual-core processor, 4GBs of RAM, a 500GB SATA drive and an Integrated Intel 3100 GMA (Graphics Media Accelerator). For Fedora, I used a Gateway GT5622 desktop with a 1.8GHz Intel Pentium E2160 dual-core CPU, 3GBs of RAM, a 400GB SATA drive, and an Intel 950 GMA.
On both systems, installing the browser took no more than five minutes. Once installed, I found that my two must-have Firefox extensions the Google Toolbar and XMarks were both working.
However, on Windows, I found that two other extensions were DOA. These were the AVG Safe Search 8.5 malware detector and the Microsoft .NET Framework Assistant 1.0. I wasn't too surprised by either one. The AVG program has had issues with other versions of Firefox and the .NET Framework program has always been a pain.
I should also note that, unlike Google Chrome, Firefox has a mature family of extensions. I really like Chrome a lot, but it's still taking baby steps when it comes to using extensions for added functionality.
On the other hand, after running Firefox for days and with multiple windows and tabs, I found that on both Windows and Linux, Firefox is finally not hogging memory. Even with the debugging code that must be in a beta, I found that Firefox is no longer leaking memory. That's good for both the browser's stability and its security.
I also noticed that Firefox has borrowed several nice improvements from Chrome. For example, it uses DNS (Domain Name System) pre-fetching so that when you click on a link you'll get to its page a bit faster.
The new Firefox also has some nice features of its own. It now supports embedded Ogg and WAV video and audio format without the need for a helper program. It also far better privacy settings so you can use your own, or any other, computer without leaving any traces behind of what you've been doing.
All-in-all, I found this beta to be a real step up from Firefox 3.0.x. Still, I find myself wishing that I could have a Firefox with Chrome's speed or Chrome that works on multiple operating systems and with Firefox's abundance of extensions. If you're already a confirmed Firefox user though you'll want to switch over to Firefox 3.5 as soon as the final version comes out. Look for it sometime in mid to late June.