I travelled to the conference from the UK last year and was similarly worried about transporting my guitar. I took a Martin DRS2 acoustic, not one of their expensive models but expensive enough if it needs replacing. My personal thought processes and experience were:
1. Make sure it is insured and check it is appropriately covered under the insurance
2. Make sure it is a guitar that I'd be ok with replacing under insurance if the worst happened, not one with emotional attachment
3. Some people said try to take on board or check at the gate - but what if you can't when you get there? Prepare to check it with other bags
4. Buy the sturdiest flight case I could reasonably afford - I wasn't sure the wooden Martin hard case would be sturdy enough. The TSA Approved Gator Case in moulded ABS that Colder mentions looked the best option to me but I couldn't get hold of one. Instead I went for a TourTech Pro ABS Acoustic Guitar Case ('fits most dreadnoughts'), which I bought online. It looked really robust in photos, description was good and the guy on the phone said my Martin should fit. When it arrived, it looked less sturdy than I'd hoped, but not bad. The internal padding was not very deep though and the guitar sat loosely inside. I decided to risk it, but pack the heck out of it with bubble wrap. By the way it had a TSA approved lock.
5. Check it in at airport with other bags and pray.
6. On check in I was glad to be told to hand it over at the 'special' luggage place rather than put it on the belt and to receive and recheck it in Atlanta in the same way before picking it up in Nashville. It did not come out on the carousel at Nashville but was brought round by hand. What happened behind the scenes? I'm probably better off not knowing.
7. On arrival at Nashville, and again at home, the guitar was completely unscathed. However, it was apparent that TSA had opened and inspected the case on both the outward and return flights. They had re-packed it ibut the sheer amount of bubble wrap caused the hinges on the case to buckle slightly after they re-packed it.
If I went again (would dearly love to, but can't afford it) then I'd do everything the same but try to find a similar case that actually fits without all the bubble wrap. I'd accept that something bad might happen and I might have to replace the guitar on insurance. I wouldn't take one that is irreplaceable.
I hope that is of some help.
p.s. I flew with Virgin Atlantic (superb) and Delta