Starting March 1st, the state of Georgia will begin eliminating the "birthday tax", or Ad Valorem, collected annually on registered vehicles.

Instead of a yearly tax, individuals who purchase a car after March 1 will simply pay a one-time sales tax up front of 6.5% (and increasing to 7% in 2015). Existing cars will continue to pay the Ad Valorem tax every year as always, so this only affects people who buy a car after March 1.

So where does the government hope to make up the lost annual revenue they collected? By picking it up from private sales of vehicles. Whereas car dealers used to collect sales tax when they sold a car, there was none collected on a car bought from an individual.

I'm not sure how this will change registering used cars in Georgia. Typically it's been very easy, you don't even really need a bill of sale. Now with them collecting 6.5-7%, I imagine they will want some more paperwork documenting the sale price. I guess it will remain to be seen.

For now if you buy a car between Jan 1 and Feb 28, you will have the option to either pay the one-time sales tax or pay the yearly Ad Valorem. The Georgia Department of Revenue has a new tax calculator you can use to estimate how much it will cost either way.

Sources:
http://georgia.gov/blog/2012-08-20/ending-annual-ad-valorem-tax
http://www.forsythnews.com/section/2/article/16115/
http://www.ajc.com/news/news/new-one-time-car-tax-raises-cost-of-private-sales/nTkJc/

Interesting stuff there Russ.  The government (local, state, and federal) is always spending beyond their means and then looking for a way to cover their bank accounts.  The Ad Valorem tax is a percentage of the value of the vehicle at the time of registration or buying a new tag.  My old air-cooled VWs are typically valued at $100 for the Ad Valorem tax and I end up paying 2 or 3 bucks tax each year.  New cars can cost you several hundred dollars each year when you get a tag.  I guess they figure that if they can collect sales tax every time a used car changes hands, they can afford to drop the Ad Velorem tax.  Folks buying NEW or nearly new cars will be happy.  Under the current system, if you are buying from a dealer, you are already paying the sales tax PLUS the Ad Velorem tax each year.  Folks who drive old clunkers will pick up the slack by paying the sales tax everytime they buy a used car.  It'll be interesting to see how this plays out.

A few years ago they tried to begin collecting sales tax from private party used car sales.  Once the public raised so much of a fuss that elected officials saw it would be the end of their public service careers, they quickly repealed the new law and refunded the sales tax that people had paid.

A couple of years ago they decided to charge a $35 fee each year for any special tag (instead of a one time fee like they always had). That year, thousands of folks turned in their special tags and the state not only lost out on the $35 fee, they had to give out a new metal tag instead of just a sticker.