The true data apocalypse will come when ISP logs are compromised and leaked (urls visited, dns lookups, tied to ip or even subscriber ids, etc), and there is enough leaked PII floating it out there to join it to people records.
With the exception of big evil things like Comcast, you might be surprised how few ISPs keep detailed logs like this. The effort to correlate them with customers is generally not worth it unless you get a subpoena, and only then is it done manually.
(UK) The new surveillance law requires web and phone companies to store everyone’s web browsing histories for 12 months and give the police, security services and official agencies unprecedented access to the data.
