[hardwaresofton]

The default-installed package management system on emacs is fantastic. You generally have to include more sources to get a lot more packages (marmalade), but it's way better than Vundle/Pathogen.

Also, IMO the real driving force behind why emacs is the best browser is the rejection of modality that was the norm (of the time).

I think a lot of people would find it ridiculous if they entered their favorite IDE and were forced into a modal scheme for text entry.