I'm excited for the possibilities this opens up, but I have some questions.

How does this service pay for itself? If its not a for-pay service how can I know you're not trying to amass a database of info to resell to marketers?

I like the idea of anonymous login, but how anonymous exactly is this? Of course I have to auth to your site so you know my IP, how long do you keep logs for? If I don't login for 6 months can I rest assured that my IP is gone from your logs and can't be tied to my account until I auth again?