It's a fantastic deal if you 1) Go to WDW often and/or 2) Normally stay in the more expensive hotels. If you normally stay in the budget hotels or off-site, it takes much longer for it to become a good deal. That said, I love that DVC has kind of forced me to improve the quality of my vacations. I like using my points at
Disneyland for staying in the Disney hotels. I like knowing that my vacation room is paid for in advance A LOT. It's been a great way to make sure that my family of hopeless procrastinators get good, relaxing vacations at the place where we have the most fun.
I can talk about it a LOT more if you want, I just try not to get too long-winded anymore.

I loooooove my DVC membership.
Dawn