This is where I stop clicking "like" on anything (I already block facebook's scripts outside of facebook itself, so don't see their "like" buttons on external sites).

I'm not giving fb's advertisers permission to plonk adverts where my contacts will see them - if I think something is worth mentioning to my contacts I'll mention it myself. If someone places an advert on my news stream because I interacted with their page, then fair enough (I can just hit unlike should I choose to terminate that "relationship"). If fb want to advertise something to my contacts "just because" then they probably have the right to do so (no doubt this is covered in the Ts & Cs we agree to by creating an account and logging in), but I don't want to be a source of (an excuse for) advertising opportunities and won't be used as one.