First, I don't believe that's technically possible to do without an explicit user opt-in, even if we wanted to implement it. Second, I've never understood why

First, I don't believe that's technically possible to do without an explicit user opt-in, even if we wanted to implement it. Second, I've never understood why people automatically assume the worst of analytics tools. No one assumes random web startups are selling their username, email and password combos to identity thieves, but if a startup collects some anonymous data for analytics, everyone's eager to assume it's both grabbing stuff that's personally identifiable and using it for some nefarious purpose. My pet theory ties this to our desire to feel important - everyone wants to believe their personal information's both valuable and interesting enough to be worth filching despite the obscene legal risks of doing so. However, it's not.