"Greyhound is a better choice between those city pairs. You can't really get to Biloxi from Atlanta by train, conviniently. The most convenient transfer point is Hattiesburg, but the bus leaves an hour before the train is supposed to get there"
Besides Hattiesburg, Picayune and Slidell are options. Give me 9 hours on Amtrak ANY DAY and drop me 50-100 miles away compared to door to door service sardined on Greyhound. Special fares to New Orleans advertised on Amtrak.com are $58. Atlanta to Slidell , also $58 (before any applicable discounts). Atlanta to Picayune 9h53m, is also $58. That 9+ hours on Amtrak means your vacation can start in Atlanta, not when you arrive at the destination. But, we all know that.
"Speaking specifically to Atlanta, though... when Atlantans want to travel, how often is it to somewhere on the Crescent's route versus somewhere like Savannah, Florida, Tennessee, etc...? As in, is Amtrak even an option for most Atlantans, or does it not go where they want to go? "
Maybe Mr. Haithcoat, had8ley, NativeSon and Mr. Harris have a better mind on this but I'd like to see it go to Savannah, Valdosta (restore and reroute the Sunset to go here), Huntsville (AL), Columbia (SC) and Nashville (TN) to give more options to connect to other trains. I would like to daytrip to Toccoa or Gainesville but the times don't work out to come back the same day. As someone mentioned on another thread, Atlanta to the mountains is a desired trip. Some snowbirds, after discovering living conditions in Florida are now halfbacks. They retired to Florida, changed their mind and move half-way back home, i.e., the mountains of GA, NC, VA and SC. So, Atlanta to the mountains and Atlanta to the coast would be very popular routes. In addition, I believe that there ought to be suburban stops (Amshacks are fine) near Duluth to the east and near Douglasville to the west. Atlanta is growing in every direction. Duluth is in Gwinnett County which has an aversion to running MARTA through there but they might have less difficulty with a stealth move by Amtrak to put up a stop.
Atlanta absorbed a large number of New Orleans (Katrina) expats so the Crescent is perfect means of going back "home". Hattiesburg seems to be a jumping off point for many of the contractors working there. A mini boom occurred in HBG. When certain Louisiana organizations wish to reach the expats they advertise in the Atlanta Journal Constitution and other local newspapers.
Thanks Rafi. I did notice your name attached to an Amtrak related picture in the AJC awhile back.