We've seen through various blog posts that Firefox 3 uses significantly less memory than Firefox 2 (and the dominant browser) and is so far the fastest browser according to Apple's SunSpider benchmark. But does this mean in the real world? What does it actually change for our users? Does it really make a difference? Actually, it does.

Take Gmail, a very popular and complex Ajax application. It's used by millions of people worldwide[1]. You can make your own lo-tech browser benchmark without even using a stopwatch and see by yourself how Firefox 3 makes a difference:

  1. Launch IE7 (yeah, I know, it hurts, but well, it's for the good cause) ;-)
  2. launch Gmail in IE7
  3. click on a message header
  4. when the message is loaded, click on the Older > link (on the top right corner of the window) to switch to the next message
  5. notice that it takes roughly half a second[2] so see the next message displayed. You can do this several time in a row to get a better sense of the actual time it takes
  6. do the same in Firefox 2. Notice that it's significantly faster (roughly twice as fast compared to IE), but you still perceive that you have to wait for the next message to show up
  7. quit Firefox 2 and launch Firefox 3 instead.
  8. repeat the test. You'll notice that now Gmail responds instantaneously.

Basically, and we would need a GMail debugging account to put actual numbers on what you have experienced, these are the results:

  1. Firefox 3 on Gmail is roughly 7 times faster than IE7
  2. Firefox 3 gives instant response. It's because it takes significantly less than 100ms to react. 100ms is the limit of what an average human being considers as "instantaneous" when using a computer application.
  3. Having Firefox 2 being almost twice as fast as IE what great. But going under that 100ms barrier with Firefox 3 suddenly makes Gmail much more usable and friendly under our new version. It's an actual improvement for millions of people, and I think that Gmail is just an example of the increasing number of innovative Ajaxy Web apps that are being built every day.

As an added bonus, this means that people using Gmail on older hardware will benefit from Firefox 3 by getting a better milage from their hardware. As a super bonus, this means that Firefox Mobile, when it will be available, will perform really well on mobile platforms where CPU and memory are more limited than on the desktop.

I just can't wait to see Firefox 3 released, so that our installed base (getting close to 200 million active users!) benefit from it. Oh, by the way, have you pledged to download Firefox 3 in order to beat the Guinness World Record?

Notes

[1] I know, I use it myself!

[2] Depending on your hardware, of course...