Also, what I expected to see was an amazing trip that I could book, each month. So in a way a sort of groupon style deal. I think if you combined that with some sort of buddy up/social network aspect where you could meet and talk to the people going on the trip you'd be on to a winner.
Perhaps you could then have a cheaper membership that gave you a discount and entitled you to first dibs on available places etc.
Just my thoughts though from scanning the site quickly. So take all advice with caution! Good luck with it!