Both, I was in high school during the Kurt Cobain era, I can tell you there was both true fans, and people who thought they liked him, but knew nothing about him or his music.

i agree i know loads of people who say they r nirvana fans but u ask them somthing/tell them about somthing that every fan should know they r like 'i dunno' sad times esp if i talk to them about bleach they r like oh i like that song :S