Probably only the most ancient of players have any recollection of what this actually is as I have not seen many Mentors these days besides my own. Recently, Producer Matsui answered a question:
The mentor-ship program was originally created for this very purpose, but as it was originally developed for beginners (you know, theidentifier when you first start out) it hasn't really been adapted to much or even widely known. I doubt any new players, or several veterans for that matter, even know of the mentor search feature.
I for one, can count on one hand the amount of times I have taken down the mentor icon since I volunteered for it 7 years ago and in all that time I've had less than 20 people ask for my guidance. I recommend expanding upon this idea and putting it out there for new/returning players to utilize more prominently.
As I mentioned earlier, very few people actually keep their mentor sign up. As such, it would be a detriment to my play-time if I had to answer questions for 20 new people/day. Share the work load and recruit new mentors. I know I do it purely for the satisfaction of helping out the lost, but I'm sure you'd get more mentors if there was a reward system. Nothing game breaking, just a thank you for what you do. Could even organize it by points by giving the new player the option to rate their mentor.
Just a thought.