That was really frustrating. As a UK Web developer at the time, I understood the ruling as preventing the use of client-side tracking technology without an opt-

That was really frustrating. As a UK Web developer at the time, I understood the ruling as preventing the use of client-side tracking technology without an opt-in; this would have included tracking cookies, supercookies, web beacons, etc., but wouldn't include non-tracking uses required for functionality, like "remember me" tickboxes. It looked like a good first step to tackling rampant privacy violation, but at the last moment the Information Commissioner caved in to bullshit claims that the ruling would cause the collapse of all Web businesses. The enforcement was changed from "not allowed unless opted-in" into "visiting a site counts as opting in". The end result is not only completely ineffective, as it basically changes nothing; it's also resulted in the profileration of ridiculous "by using our site you agree to our use of cookies" messages, which just annoy without doing anything.