Using a sample of 50 anonymous blogs pulled from discussion forums and Google news, only 14 were using Google Analytics, much less than the average. Half of those, about 15% of the total, were sharing an analytics ID with one or more other domains.
In about 30 minutes of searching, using only Google and eWhois, I was able to discover the identities of seven of the anonymous or pseudonymous bloggers, and in two cases, their employers. One blog about Anonymous' hacking operations could easily be tracked to the founder's consulting firm, while another tracking Mexican cartels was tied to a second domain with the name and address of a San Diego man.
The middle part of a Google Analytics ID (i.e. the X part in
UA-XXXXXXX-NN) — which is always visible on a page using Google Analytics — is uniquely tied to your Google Analytics account, and shared among the individual sites you’ve set up.
Semi-connected in my mind: an Anonymous-related group called off a doxing operation against a Latin American drug cartel after the cartel a) kidnapped an Anonymous member, b) claimed to have identified other members, and c) sent out death threats.
Playing with fire — i.e. staying truly anonymous online — is tough.