>Browsers are a commodity product. They all pretty much look the same and feel the same. All browsers work pretty well, and being slightly faster or using slightly less memory is unlikely to sway users.

Not really. Buy a cheap laptop and see Firefox freeze all the time rendering pages while Chrome keeps up like a champ.

All your remaining users are the die-hard users like me, who stay because they like the addons, or some other thing. But Mozilla has decided they'll remove those too, so...