We do! If your friend entered your email address in the appropriate field the first time they signed in (and your account was active at the time), you should get one additional month of service added to your account during the first week of their second month, provided that they don't cancel. If this doesn't happen, please let us know so we can resolve the issue.
Thanks for recommending us to someone else! We love hearing that people like our service enough to recommend it to others.