Thanks for all the great thoughts here. I checked out the handicaching.com website and added a review for a cache I just found yesterday.
I wonder if they would be able to work with Groundspeak to add their link to the cache page on geocaching.com. Then, we could just click the "check accessibility" link and other cachers would also be made more aware of access issues just by their own curiosity about the link. Just an idea.
I am a paraplegic who uses a wheelchair full-time. I often cache with my wife and son, so they sometimes need to make the final grab once we locate the cache. Sometimes, I go on my own, however, so access is important. Yesterday, for example, I found 4 caches but could only reach one of them. Since I was on my own, I had to leave the other 3 for another day when my family is with me. Still, I got to see some nice viewpoints.
Anther idea that might be helpful is for the cache hiding guidelines on geocaching.com to include something like this: "If, when you are hiding your cache, you have a choice of good hiding spots, please consider choosing the one that is most accessible to someone using a wheelchair."
Anyway, it's great to see and hear from other disabled cachers.