[chkuendig]

No, I meant across different properties of different publishers. I assume that's still only possible with browser fingerprinting, IPs etc.

So blocking third-party cookies is a good start to avoid tracking across different publishers (which is the big no-no for me, the fact that a single publisher knows what i read of his is not such a big issue and not that different to what has always been done by just crawling the ht_access logs...)