Exactly what is it that convinces a Windows 7 user to drop theWeb browser that came with her operating system - Internet Explorer- and try one of its many free competitors?  The very name"Firefox" implies both speed and savvy, two factors its predecessor- Netscape Navigator - did not always possess.  "Faster" and"better looking" are the two factors that make folks trade up for asports car, though with a Web browser, "free" is a nice incentiveyou don't find in the automotive market.

Last month, Microsoft demonstrated that it is indeed capable ofrobbing Firefox of all its persuasion points, witha public betaof IE9 that is faster and smoother than anything Mozilla hasever produced.  If IE9 is already fast, simple enough to use,and even good looking, the incentive for consumers to try not justFirefox but any other alternative, could evaporate.

In the most recent browser performance tests conducted byIngenus LLC on October 8, Mozilla's public beta of Firefox 4.0 Beta6 continues to lag behind Microsoft's public beta of InternetExplorer 9 by 20% overall.  Using the performance of the 2008model Firefox 3.0.19 as an index (1.000), Mozilla's current stableFirefox 3.6.10 release scores a2.199 overall,representing better than twice the performance of itspredecessor.  Firefox 4.0 Beta 6 scores a3.067 on the same tests; and it should be worthnoting that the ability for any mechanical product to gain about100% performance per year is an extraordinary achievement.

But in a field of extraordinary players, this milestone couldget lost in the shadows.  IE9 scores a3.692on the same suite of tests, catapulting itself over IE8's score of1.277 and making room for itself as a truecontender.

Being just a contender - just capable enough to fight the battle- may be all Microsoft needs to win this war.  While noteveryone seriously cares about the performance of his Web browseror his refrigerator or his lawnmower, in recent months, the numberof folks whodo care has grown.  Historically, it'sthe non-caring group that has represented Microsoft's base; infact, this year the single loudest evangelist preaching the virtuesof kicking off the mortal, rotten coil that is IE version 6, hasbeen Microsoft itself, going so far last March as tosend flowers to a mock IE6 funeral.

For the other group, the urge to use Anything But Microsoftremains strong, including for office workers who feel stuck withWindows every day.  That urge has sustained Mozilla's corecustomer base up to now.  But Mozilla's place as the standardbearer for alternatives is now under concerted attack by all threenon-Microsoft rivals, with the smallest of them all carrying thebiggest guns to the fight.

An exhaustive battery of tests on the latest developers'snapshot of Opera Software's latest 10.7 reveals a browser bettersuited for running modern Web applications than even Google'sfastest developers' build of Chrome.  Last Friday, thatsnapshot build scored a colossal5.167 overall,toppling both the4.419 score posted by thecurrent stable Opera 10.62, and Google Chrome's fastest score: the4.825 posted by development build 7.0.544.0.

Ingenus' tests account for browser performance in four primarycategories: JavaScript computational speed (30%); HTML/DOM textrendering and HTML/SVG/Canvas graphics rendering speeds (30%);"scalability," which Ingenus defines in this context as the abilityto maintain or improve performance as workloads scale up (20%); andefficient use of CPU and memory (20%).  All of these factorscombine to affect perceived page load speeds, but no single test'sresults can be impacted by the relative speed of the Internetconnection, which is an independent and unpredictable variable.

Four years ago, Opera Software lit the fuse that sparked thewhole "speed is good" argument in the Web browser field.  ButMozilla, Google, and Apple all answered back, leaving Opera behindas an also-ran, even fueling speculation that Opera could justsimply quit.  IndyCar fans will appreciate this analogy: If Firefox 3.5 wasDanicaPatrick, Opera 9 wasMilka Duno.

Then last spring, Opera changed drivers, changed engines, andchanged everything.  It introduced a JavaScript enginecode-named Carakan that replaced its stack-based processing systemwith a full slate of registers and a bytecode generator, which isthe difference between a pocket calculator and an iPhone. Suddenly Opera had an engine with the ability to digest JavaScriptintonative code for processors, one big step ahead of theintermediate bytecode that managed code interpreters typicallyproduce.  WhenOpera firstannounced Carakan in February 2009, developers promised theability to effectively digest entire segments of JavaScriptprograms into something that resembled assembly language.

Opera's developers have been more quiet these days than theywere last year, but based on what we're seeing from the snapshots,it's because they're very busy.  Ingenus' tests indicate thatthose "entire segments" of code selected for heavy pre-digestion,in the next version 10.7, will include many of the open sourceJavaScript libraries used by Web apps developers to generateworld-class, in-browser applications such as word processors, photopaint utilities, and even movie editors.  Web developers whobuild AJAX apps that listen for local events are adopting thejQuery library more and more; and Opera 10.7's performance withjQuery and several other libraries is nothing short ofastonishing.

For its latest tests, Ingenus re-engineeredthe open sourceSlickSpeed selectors test to account for the newest versions ofJS libraries, and also to give each one more of a workout. The new test battery,which you can see andtry for yourself on this page, gauges the amount of time ittakes for a browser to process 64 different standard CSS3selectors, both natively and with the aid of the most recentversions of ten different libraries includingjQuery, the popularMooTools, and the latest build ofselector engine Sizzle by jQuerycreator John Resig.

Opera 10.7's SlickSpeed scores are nothing short ofastonishing.  Here's the full scale of it in a nutshell: Not long ago, the average CSS3 selector took the jQuery libraryabout 250 ms to execute.  When Microsoft unexpectedly threwits support behind jQuery, it improved IE8's performance with thatlibrary to approach par for the course.  Now IE8 executes aselector with jQuery 1.4.2 in 228.72 ms.  Firefox 3.0.19 (theindex browser) takes 171.9 ms on average, and Firefox 3.6.10accelerates that speed all the way to 39.83 ms.

Throwing down the gauntlet, Google Chrome's performance withjQuery of late has seen posted times of between 11 and 12 ms, whichjust last month would be called astonishing.  Opera 10.62performs well at 20.34 ms, but well behind even Apple Safari 5.0.2at 16.02 ms.

Here's where Opera 10.7 picks up the gauntlet and throws itoverboard, posting an average time of3.69 ms onaverage.  Other libraries also share in Opera's switch fromimpulse to warp drive: Sencha's Ext 3.2.1 JSlibrary performance boosts from 20.66 ms (10.62) to2.98ms (10.7);NWMatcher 1.2.2performance surges from 19.79 ms (10.62) to3.61ms (10.7); and Resig's Sizzle library finds its powderkeg, blasting from 19.4 ms (10.62) to3.1 ms(10.7).

It's surges like these that lead to Opera 10.7's unbelievablerelative score of20.407 on the new SlickSpeedbattery, compared to its nearest rival, the latest stable GoogleChrome 6.0.472.63 with8.822.  The latestdaily development build of Firefox 4 Beta 8 (less stable than the"public" Beta 6, though still openly downloadable) manages only3.353 on this same battery.

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