No, Cluin, I won't let the ISP off so easily. They claim they are not responsible for the content carried, yet it is precisely that content that they advertise when they want to increase their subscriptions! How many times do you see their ads mentioning "faster download times" or "access to music and films from all over the world"...So, guilty as charged, in my book.
Having said that, SOCAN's move is also an admission of their inability to monitor rights use effectively anyway. And the MCPS-PRS alliance in the UK are no better.
Which leaves us in a world where the artist/author/performer has to be constantly on the alert to protect his/her rights. But then we live in a society where you are only criminal if you are caught, so who am I to moralise...