I use Scrivener for writing but haven't used it to plan out a novel. I got the program after succeeding in nanowrimo one year and got the discount for it from making 50k+. It's handy, especially for keeping my different drafts, edit notes and such on a single novel all in one item. I prep just on WDC with a book item.

Then again, I am not much of a planner novel wise either. It's fun to prep and keeps me thinking about the novel. But when I write I just sit down and write, forgetting all the notes I made beforehand. We all find our own ways to get where we want to go.