> Fact: Recording user behavior most certainly is a privacy issue...

> My opinion: ...and it should be both disclosed and opt-in.

And, perhaps, avoided completely–once your shop has resources to spare for in-house testing and usability research.

Fact: Recording user behavior is extremely common...

My opinion: ...and users shouldn't act surprised by it.

Almost all websites have analytics these days. Agreed, it should be disclosed but making it opt-in would render analytics useless as less than 1% people would agree to it. Most analytics is not even a privacy issue as clickthroughs and bounce rates do not carry any personal fingerprints.