Firefox is far from becoming "more and more irrelevant". Just because you've switched to an alternate browser doesn't mean the rest of the world has. Chrome may be incrementally gaining some share, but it's mostly at the expense of IE. Firefox has almost 25% of the market, while Chrome is 5%.
I've been using Chrome / Chromium exclusively since its release, primarily due to the simple, uncluttered UI and blazing speed. It was a breath of fresh air, and I switched readily.
But something changed with the recent Firefox 4 betas. The browser feels fast, again, and the UI seems more reasonable. I find Panorama useful. And slowly, Firefox is winning me back. In time, I think it may win back other developers, too. And if it does, I could easily see a fairly stable equilibrium developing between the two browsers.
Firefox needed the competition from Chrome, and in many ways, it's starting to meet that challenge.
Chrome currently has 16.5 percent global usage share, IE has 45 percent. FF's share remains stable at 31 percent. Chrome gained ten percent points in the last year, while IE lost ten percent points. At its current growth rate, Chrome will pass FF in 15 months.
