Even better than that is pressure to keep addons/plugins/whatever up to date.
I think there's some good precedence for that with Firefox who (still?) deliberately broke all their extension compatibilities on every release, and contrary to that Wordpress who've led to a fully automated exploit ecosystem.
I don't know about Firefox doing that on purpose, but the addon that I've written (Link Exposé) has seen several releases of firefox (19.* to 24.*) without having to do an (api) "update". It's written using the new jetpack SDK (now "Add-on SDK") - and there is a commitment to keeping that api stable.
I think there's some good precedence for that with Firefox who (still?) deliberately broke all their extension compatibilities on every release, and contrary to that Wordpress who've led to a fully automated exploit ecosystem.