As I implied in my previous post, I don’t want to simply repeat all the great comments about Firefox 3 that everyone else is posting; better to read them in the original and not get them second-hand from me. But then I thought: instead of rehashing others’ posts, perhaps I can rehash my own? I’m quite fond of the theories of innovation created and popularized by Clayton Christensen, including his concept of “disruptive” innovations versus “sustaining” innovations, and have written a number of posts discussing those theories in the context of Mozilla and Firefox. What better occasion than the launch of Firefox 3 to write yet another?

In Christensen’s theory sustaining innovations are those intended to satisfy the most demanding users, along the product dimensions that they most value. Viewed in this light Firefox 3 represents sustaining innovation at its best. Demanding users of the web open lots of browser windows and tabs, run complicated web applications, are looking for more ways to improve their productivity when browsing, want a browser that preserves their security rather than threatening it, and like to customize browsers to their own exacting specifications. Firefox 3 meets their demands with (among other things) improved JavaScript performance and lower memory usage, productivity enhancers like the “awesome bar,” better protection against malware and phishing attempts and improved identification for SSL-enabled sites, and an ever-expanding collection of useful extensions.

Big deal, some might say: “Firefox 3 is just an improved browser, nothing more. When do we get the really exciting stuff?” I addressed this view in a post some time ago discussing the Tamarin project:

We’re conditioned to look for “world changing,” “break the mold” developments in technology and to dismiss merely “incremental” improvements. . . . [We] think “disruptive innovations” are sexy, and “sustaining innovations” are not.

I believe this is a serious mistake. First, the terms “disruptive” and “sustaining” aren’t indicators of the technical merit of innovations; they simply indicate . . . the degree to which innovations better satisfy the needs of existing customers (sustaining innovations) vs. appealing to new customers (disruptive innovations). . . .

Second, the cumulative impact of multiple sustaining innovations can be quite large, and can enable new disruptive innovations to take root and flourish. For example, as many people have pointed out, at least in theory Web 2.0-style applications could have been developed many years before they in fact appeared. The advent of Web 2.0 as we know it was really a function of multiple sustaining innovations that accumulated over time and interacted together . . .

The individual innovations were relatively small: a minor cost or performance improvement made, a few more browser bugs fixed or new browser features added. . . . But in toto these innovations added up to nothing less than a revolution in the way the web can be used.

In this sense everyone who contributes to the Mozilla project—fixing a Mozilla bug, making a performance improvement in Mozilla code (no matter how small), enabling Mozilla-based products to pass yet another standards compliance test, writing a Mozilla test case, creating or revising a Mozilla documentation page, and so on—helps change the future of the web and advance our goal of promoting choice and innovation on the Internet, to the ultimate benefit of everyone.

Firefox 3 is the latest example of the importance of sustaining innovation in building the Internet of the future; may there be many more!