Ramifications of Walking Away in Georgia

I am seeking some insight but certainly will not rely on the answers but it will give me some thought. I purchased my townhome in 2006 at the height of the Atlanta real estate market, on a property that was talked "down" to $320,000. My mortgage is $285,000 and the appraisal for a refinance came in at $140,000!! Incredibly unbelievable if it wasn't true.
This being said, my worry is a mortgage of over $2,000 a month and property taxes that continue to rise. Even if the market rebounds, albeit slowly, my property will not be increasing over 100% for sure. If I do walk away, are there ramifications other than credit and steps the bank would take such as wage garnishment to get the money back? That is my biggest concern.

Any insight would be great. Thank you.