The color for Mellow Corn comes from the 4 years it spends in the barrel. So, it's much older than Georgia Moon, which I think is about 1 month old. The Mellow Corn is actually pretty good stuff.
Unless we are talking about a different Georgia Moon, a version that spends a month in wood, GM can't be said to be aged at all. It'll taste the same out of the jar as it did off the still, accept of course for the reduction in proof.