A lot of people take I-285 to Camp Creek Parkway to get to the airport, which is fine, but I've found the traffic lights on Camp Creek can be annoying. When you are late for a flight every traffic light seems to stay red forever! Overall I think it's quicker and easier to use Langford Parkway instead of Camp Creek Parkway.
My "shortcut" is a longer route (33 miles from Ga. 400 at I-285 to the airport exit on I-85) compared to going through downtown (21 miles from GA 400 at I-285 to the airport exit on I-85), but trust me, there's a greater chance of getting stuck downtown, than there is on the west side of I-285.
Of course this is all dependent on traffic conditions at the time you want to go. You should always check georgia-navigator.com or wsbradio.com before you leave the house to make sure I-285 isn't too bad. If you are on Twitter, you definitely need to follow @ajcwsbtraffic. And once you are in your car, tune in AM 750 or 95.5 FM to monitor current traffic conditions. Usually the west side of I-285 south of I-20 is not jammed unless there is an accident, so odds are you'll be fine.
If you live on the east side of town, this "shortcut" probably isn't your best option. You might want to take I-20 westbound to I-75/85, then head south to the airport.
If you live in the southern suburbs consider yourself lucky. I-85 and I-75 are usually okay heading northbound to the airport.