RA> It *has* started, and as more and more use this option it will be only a RA> matter of time before they shart showing up in your area. You can't view RA> this cache information unless you pay.
But you don't *have* to pay to participate in Geocaching. There are thousands of other caches on the site that do not require a subscription to view. And, you're assuming that a number of people will create members only caches. I don't think that's going to be the case. I still don't understand what the benefit is, unless Geocaching.com is going to pay you a percentage based on # of times your cache has been found, # of members only caches you hide, or something else.
The only reason I can think of that would prompt me to create a members only cache is if I owned (or really cared about) the property where the cache was hidden and it was just getting too darned many people. And in that case, I'd probably move or remove the cache. Maybe I'm just lucky to live in an area that hasn't been inundated with caches yet. I do care about the parks where I've hidden my caches. My caches exposed people to a couple of parks that many people didn't know existed, one within a 15 minute drive of the city. But there isn't a steady stream of people hiking to my caches...