Often, as T.S. Eliot wrote, words are inadequate. I’ve recently decided that Firefox 4 will be my last release working for Mozilla. Like Eliot’s lover, let me struggle to find the words explaining why.

Almost six years ago, when I left IBM Canada for Mozilla, my manager assured me I’d be back at Big Blue in a couple of years. “It’s just a web browser,” he said, “how much work can there be?”

A lot, it turns out. I knew very little about the technology used to drive the Web, about open source communities, about how to ship software, or how to not cause the trees to go orange by revving an entity name when changing a string.

I have had the great privilege to work with this community of employees, contributors, volunteers and enthusiasts in order to ship six “upgrades to the Web” from Firefox 1.5 through to the soon to be released Firefox 4. I am indebted to so many people at Mozilla for what they have had the generousity to teach me, for giving me the trust and opportunity to learn, and for some incredible memories, friendships and experiences.

There comes a time, however, when one needs to “just keep movin’ on.” I’ve been getting antsy for the past few months, as some people may have noticed, and have decided that it’s time to challenge myself by jumping into an industry about which I know next to nothing. Some things will be familiar, of course (I’ll be managing product strategy for a small team of incredibly smart people, developing advanced, disruptive technology in a stagnant market with a dominant market leader) but almost everything else will be different, and I’m looking forward to the opportunity to learn and grow. I expect that you’ll see me trying to see how I can apply some of the tools I’ve developed here to that industry, too