It can take a week
tscwait485,
I have known notices to take about a week and sometimes more. Wait till next week and then start to inquire.
The only doubt I have is that your EB3 case was "technically" not supposed to have been approved because of the unavailabity of visas so you want to make sure that the email was not sent in error. If you do not receive the written approval notice within the next week it might indicate that something weird is going on. Don't get me wrong, I truly hope you have been approved but with TSC you always have to watchout. That has been my experience thus far.
regards,
saras