I've talked before about how I wish we'd all move on from the ARMv6 architecture, now that we're already getting so close to the launch of the 64 bit ARMv8 architecture within the next 2 years. The sad reality is that most devices, especially the low-end ones, are still on this decade old architecture.
Hopefully, with the launch of Cortex A7 next year, which is built on ARMv7, we'll finally start to forget about ARMv6, at least for new devices. Google has already started doing that with Chrome, for example, which only supports the ARMv7 architecture, even if you have Android 4.0 on your phone.
Until recently, Firefox for Android only supported ARMv7 as well, but seeing how they started so late in the game, more effort is required of them if they want to succeed. So starting with version 16 of Firefox Mobile (currently on version 13), they are building in support for the ARMv6 architecture as well.
What does this mean for Android users with lower end phones that have ARM11 (ARMv6) processors typically under 1GHz? It means that even though you can't use Chrome, you now still have a rock-solid open-source browser choice for those low-end devices, that gets updated just as often as Chrome. You can also synchronize it with your desktop Firefox, in case you were worried about missing out on this feature from Chrome.
As mentioned above, support for ARMv6 is available only in the nightly build of Firefox 16 for mobile, but you can get it from Mozilla right now. Those of you who have devices with at least a 1 Ghz processor (ARMv7) can also try the latest stable version of Firefox for Android.