Having read a few more articles[1] I should correct myself and say that the majority of those which explain how Gatekeeper will be implemented in relation to the "File Quarantine" feature state that the signature check will only apply the /first/ time that a program is run.

Collectively blacklisting all the works of a developer based on trouble with a single app is still a thing, though.

[1] http://www.macworld.com/article/165408/2012/02/mountain_lion...