ZAP- Could you direct me to those job postings? I'm definitely interested in seeing those, since I've never seen salaries posted for ADR jobs.
ADR is my sole reason for going to law school, but I want to be a full-time professional neutral. It's not really something that you can go into right out of law school anyway though. The usual path is to specialize in a field that has a high utilization of ADR and act as an advocate, then if you haven't pissed off too many people on the other side, start taking on neutral work. A large percentage of neutrals also have another source of income, commonly as a college faculty member.
I think ADR can definitely be lucrative though. A friend of mine works for a BigLaw firm, mostly doing labor arbitration hearings. Entry salary out of law school...$143K. When I go to arbitration, we have to pay the arbitrator $1500/day not just for hearings, but also to study the case and write a decisison. They just tell you the number of days they worked on your case, and you just have to assume they're telling the truth! Even better...a lot of the cases settle right before the hearing starts and the arbitrator still gets his $1500.
I'm not sure what I mean, honestly. 
I'm not too well-versed in ADR. I only looked into the earnings for ADR-specialists because I was toying with the idea at one point of going to Pepperdine as well as Ohio State, and both have top ADR programs. But I was looking at job-postings, and most of them were in the 40,000-70,000 range, or sometimes even lower. I decided that if I was going into law, there had to be something that would interest me that would pay more. Besides, for whatever reason, as stands right now I don't find the idea of ADR particularly invigorating.