Bounce handling not working
Please do NOT use a gmail address for the bounces, it won't work (a google app email is fine however).

It will fail you in two different but both bad ways:


if you use mail() or a local smtp mailer for your outbound, you are trying to send an email from your civicrm server as being from a gmail email, something that google said is not allowed (SPF record) and it will mostly end up in the spam folder of the recipient (or be flat out rejected).
if you do use google smtp as mail servers, they will prevent you to send too many emails (the too many is going to be changed over time, but is pretty much guaranteed to be above the number of emails you want to send)


For your specific issue (and for others that use google apps): check the spam folder see if the bounced emails are there, and add a filter to these emails stay on your inbox, they will often be seen as spams by default until you add filters.