As a Subscriber, you will receive access to certain parts of the site that are hidden from others. You'll also get email updates when new content is available on the site or existing content is updated.
When logged in, you'll no longer see this request to subscribe.
I'm too lazy to collect any information about you other than the data you submit when you subscribe, which I will never intentionally share with anyone.
As usual, Google and other entities may also collect information about you during your visit.
If this policy changes, I'll let you know.