The New York Times uses libraries (versions) A,B,C, and D. Wikileaks uses A,B,D and F. I see that you have A,B,D and F cached - that allows me to rule out the NYT and predict with some degree of confidence that you visited Wikileaks.

You can make up theoretical models for how many popular libraries there are, or how many sites, and say this should or shouldn't be possible. I haven't seen any such models, but advertisers were definitely using this technique in the wild so the models that say it's impossible are all wrong.

Adding noise to a small sample of requests doesn't buy you that much entropy - the signal is a little noisy anyway.