Reviewed my GMail activity for contact info in my contact's signature line, and added into Google Contacts. Neat! Also, since I have 2 other Google Accounts, setup the same to pull them into my main address book. I naturally signed up premium as I am in sales, a contact sport. A must have for ANYONE in sales using GMail as a primary tool.
Actually had the developer emailing me to solicit input, answer questions. Amazing support. Cannot say enough good stuff. Not only did I sign up, signed up my boss as well.