Firefox 3.5 is a major improvement over Firefox 3, though casual users probably won't notice any difference. For many people, the browser wars are all about one thing: speed. There's no doubt that version 3.5 is faster than version 3, thanks to the new JavaScript engine, but it still frequently crashes - at least it does on my Vista machine running Flash-based sites. If you're a Firefox user you should definitely upgrade. Personally, I prefer the simplicity and reliability of Google's Chrome. Considering Mozilla has been working on the browser for a year, it has already announced it will patch the 1-day-old Firefox 3.5 in the next few weeks to stamp out several bugs that went unfixed in the final version. This is typical of open-source software. Firefox 3.5.1, which Mozilla intends to deliver in mid-to-late July, will include fixes for at least three bugs and 'topcrashes,' the term the company uses to describe the frequently-reported crashes. Like many applications, Firefox asks users to report crashes by displaying a prompt after the browser goes down. One of the topcrashes scheduled for a fix involves TraceMonkey, the new, faster JavaScript engine.