I think it has been newely implemented:
Not much changed. Most users banned for plagiarism will remain banned and new ones will still get a permaban.
There's been no policy change. redsn0w wasn't permanently banned due to several factors which made me think that permabanning him would be a net negative for the forum. Nobody is banned strictly because of "the rules"; it's always handled case-by-case, but almost always, plagiarists deserve to be permabanned.
If you think that a ban should be ended, make your case in a new topic from a "good for the forum as a whole" perspective.