I discovered this blog post from Mark Finkle yesterday and could not believe my eyes... This is exactly what Mozilla should not do, because it is an extremely confusing message to people willing to build standalone apps on Gecko and integrators. Tech deciders will not understand the difference between firefox launching a standalone chrome and xulrunner doing the same because they NEVER heard of xulrunner in the press. When I constantly and consistently say that XULrunner is an orphan child in terms of marketing and PR, trust me, I see the side-effects of that every day.

With that move, Firefox will be seen as a platform. And it isn't. Because third-party apps based on a platform CANNOT stand automated updates of the platform itself, CANNOT stand a six months support only after the next major release.

MozCo, please, you're not thinking enough about the ecosystem around you and you are hurting it. Whatever was the good reason feature-wise for that enhancement - but I can't find any in the bug itself - this move seems to me dangerous, and not desirable.