Permanent ban : Fantasists who write fake reviews. Anyone who brags about hurting or bullying WG's. Also anyone posting rape type reviews, (a good example of this is currently being discussed in the W. Mids section). Basically, anyone who comes across as a 'wrong un'
Temp ban : Someone who temporarily loses his/her temper, has a meltdown, abuses mods/members in the heat of the moment, but is otherwise, generally a good person/contributor, and shows remorse.
Oh, and as regards WG's. Permanent ban for outing punters, disrespecting mods/this site. Temp ban for temporary loss of control, (being wound up by a member for example).