The folks at Firefox have deemed the changes in this incarnation of the popular Firefox browser significant enough to skip the planned version 3.1 and instead bump up the release number to 3.5. And it's a big improvement. By its appearance, you'd be hard pressed to tell how Firefox 3.5 differs from 3.0, but it's what's inside that counts. 3.5 builds on everything that made the previous versions of Firefox great, like the myriad extensions and themes and the "awesome" address bar for quickly getting where you're going on the Web. The result? An impressive piece of software gets even better.