A lot of my stories have gotten longer lately too, which is perhaps a sign I'm learning how to tell a plot and not just a story. Or I've just gotten more long-winded. Overall, comparing word count to when I first started writing fic, my stories get longer and longer. It might be a confidence thing. When I started out, I was sort of trying not to bother anyone, and now that I know people enjoy what I write, I feel more comfortable taking up more of their time. :p