Mods are very busy around these forums, there are several topics in that forum and a very scary place to walk into. A lot of people post there, and it will take some time.
It would take around 4-5 days at the max. If not, wait a bit more, then if it doesn't appear contat the same mod. Just don't be rude and say stuff like, "WTF. WHERE IS MY THREAD?!?!?!?! IT NEVER GOT APPROVED!!!! AND IT'S BEEN [insert how many days]!!!!!"
This would be bad and they would not respond to you're PM. Hope I helped, if any questions, PM me.