If its Gwinnett Co. you're OK. They have a 20day grace period from your court date issued on your ticket. Meaning there wont be a bench warrant for you yet. Bet thing is to go up there and tell them you forgot about the date and that you want to take care of it in court and that you'll need a new court date, they'll give it to you. I have done it a couple times and been ok.

Also, get your tag taken care of, and when you go back in, physically take the tag off your car and take it along with your receipt of payment for the renewed tag in and show the judge. Plead guilty, it wont be any points since its not a moving violation (im pretty sure, but you can ask the court solicitor if it is a moving violation, but im about 98%sure its not)