Went to Brake Check (*cringe*.. I hate going to chain places like that...)
and had their free brake inspection. They told me the front rotors were
warped and pads hosed as a result. The rear drums needed turned, but the
shoes were OK. Just needed a good cleaning/servicing. Anyhow, they said
the "popping" HAD to be coming from the front shocks. Said they were shot.
Didn't make a bit of sense to me. I said OK, and said not to bother
replacing them -- I could do it much cheaper and with better shocks. The
guy said he understood.

So, we left and drove around quite a bit in stop and go traffic -- not a
single pop. I have not replaced the shocks yet, but no popping. I thought
it might be those rear brakes... I'm going to replace the shocks anyway as
the rear ones are leaking.

Thanks again for the help everyone!

Eric