Although Firefox is king of the extensions, IE8 has a few interesting ideas built into the browser. Its Accelerators are plugins that essentially bring the power of web services to the context menu so, for example, if you right-click on a link you can choose to blog it, email it, translate it and so on. It's context-sensitive, so some content will give you the ability to define text with Encarta or map an address with Live Maps. Firefox gets something similar via the impressive Ubiquity add-on, but with IE the basic features are already in the browser.
IE also gets Web Slices, which enable you to subscribe to part of a web page - designer permitting - and make it pop out of the Favorites bar without actually visiting the page. We're not entirely sure how useful this is, but it does look nice.
Chrome comes with Google Gears built-in, and that's much more interesting than Web Slices. Gears enables web services such as Google Docs to run offline as well as online, and while Gears is available for everything from Windows to mobile phones (as well as Firefox and IE) it's nice to have it in the browser from the get-go. It's not just useful for Google's own services, although of course that's why it's there; platforms such as WordPress can also use Gears to speed things up. With Chrome, you can save web applications as desktop shortcuts and open them without all the browser buttons, making them look much the same as standard desktop applications - although you'll need to enable their offline modes if you want to use them when you're not connected.
Performance
WINNER: CHROME
For everyday browsing, Chrome feels quicker and snappier - but when we compared each browser's launch times and load times for the same set of web pages there wasn't a substantial difference on our Core 2 Duo machine. On our ancient laptop, however, Chrome was noticeably faster - and we can't wait to try the Mac version, because Firefox on OS X eventually gets so depressed it kills itself.
We decided to benchmark each browser by running the Sunspider JavaScript tests, which attempt to measure real-world JavaScript performance, and we also recorded the memory footprint of each browser with one tab open and with ten. The results were interesting, to say the least.
Sunspider benchmarks (lower numbers are better)
Firefox 3.1 - 1771.4ms
IE8 - 6837.6ms
Chrome - 1923.0ms
There's no doubt that Chrome gave IE8 a spanking, but it actually lagged behind Firefox. We ran the benchmarks again just to make sure.
Second Sunspider benchmarks (lower numbers are better)
Firefox 3.1 - 1942.5ms
IE8 - 6947.0ms
Chrome - 1980.0ms
Then we loaded up a collection of ten different websites - blogs, news sites, YouTube, Google Mail and so on - and measured each browser's memory footprint. The results were:
Memory Footprint (ten tabs)
Firefox 3.1 - 91MB
IE8 - 230MB
Chrome - 141MB
With a single open tab IE was once again the hungriest, but this time we found Chrome's footprint to be positively titchy, with little difference between Firefox and IE.
Memory Footprint (single tab)
Firefox 3.1 - 50MB
IE8 - 59MB
Chrome - 22MB
Although we didn't find any significant difference in load times or page rendering times on our test machine, that's probably because it has a Windows Experience Index of 5.5 and can run Crysis without bursting into tears. Things are very different on a less powerful machine, as we discovered when we blew the dust off our laptop - a machine with an Experience Index of 2.2 and less horsepower than a badger. This time, the differences were dramatic.
Launch time
Firefox - 37s
Chrome - 15s
IE8 - n/a
