Wow are you a US publisher ? I had a friend apply 4 days ago (on weds) and they were approved on friday
With smaller sites they tend to take a while to accept, with larger sites they will accept them within 2-3 business days sometimes.
I think it depends on the number of application they currently received. But be patient, and good luck.
US publisher, applied almost 3 weeks ago with a good sized site (4 years old, PR6, etc), and still nothing either.