Ditto to the "fun" comments. But, I will add that I think the more you ride off road singletrack, the more you will want to get a full-on mountain bike. It really makes a difference. I road and trained on a hybrid for a while around St. Louis before moving to the Denver area. Now, I ride a full-on mountain bike in the mountains, train on a sweet single-speed on the road, and commute/tour with a full touring bike. Three bikes seems like a lot to someone like me, but I’ve found that the "fun factor" goes up quite a bit when you ride a specialized bike that you’ve picked out with care.