I've put the latest betas of Firefox 3 and IE8 to the test, and the results are clear: Firefox 3 is the superior browser. Its new features make browsing the Web easier, faster, safer, and easier to customize --- and the memory leak problem seems to have been fixed. IE8, on the other hand, offers some flashy new tools, but for everyday browsing, Firefox remains superior.
You'll notice the most obvious change to Firefox as soon as you load it --- it has a more modern-looking upper left corner with icons for forward, back, reload, and stop. The forward and back buttons now have a 3D chiseled look, bringing what had been a tired-looking 2D interface into the modern age. (Note: I reviewed the Vista version.)
Unfortunately, though, the Home icon has been moved from Navigation toolbar to the Bookmarks toolbar. That means that if you're someone, like me, who doesn't use the Bookmarks toolbar, you'll no longer have access to your Home button. Let's hope this changes; that doesn't make much sense.
In Firefox 3, the Navigation toolbar has been significantly powered up. There is now a star icon on the far right hand of the address bar; click it and you'll bookmark the site you're currently visiting. When you bookmark the site, or visit a site you've already bookmarked, the star is gold; otherwise it is grey. To edit the bookmark, for example, to change its folder, add tags, and so on, click the star after it's turned gold.
Also useful is a new security feature tied to the Address bar. Click the favicon of the site you're visiting on the leftmost side of the Address bar and you'll be told whether the site you're currently visiting has been "verified" using its Extended Validation (EV) SSL certificate. Only some sites use this, so it's only moderately useful. However, some e-commerce sites, such as PayPal, do use it, and that's where it comes in handy.
Big news is that Firefox 3 seems to be faster than Firefox 2, and the memory problem may have been licked. With Firefox 2, the longer you browse, the more memory the browser uses, and the slower it becomes. I haven't found that to be the case with Firefox 3.
There are a lot of other useful features in Firefox 3, such as a beefed-up Download Manager that lets you search through downloaded files, that will resume broken downloads, and that integrates with your anti-virus software so that it check for viruses right within the manager.
Why Firefox 3 beats IE8
IE8 includes some nifty new features, such as WebSlices, which is like RSS on steroids. But WebSlices will only be useful if developers write them, and it's not clear that will happen.
Another nice new IE8 features are Activities, which powers up the Internet Explorer right-click menu. Hover your mouse over an item, or highlight the item, and right-click and a list of actions appear, such as mapping the highlighted term, translating it, defining it, and so on. Depending on the choice you make, you may see a preview screen of your action right on the Web page, such as displaying a small map. This is quite useful, but again, only useful if a whole ecosystem of services springs up around it. And again, it's not clear whether that will happen.
The bottom line is that Firefox 3's new features are aimed at making everyday browsing better and simpler, while IE8's are peripheral to the browsing experience. So Firefox 3, not IE8, is my next-generation browser of choice. I'm guessing that it will be yours as well.