First off, it introduced me to dungeons. Shortly therafter, I realized that I'm not a drama/actor player (in Robin Laws' player types, later co-opted by the 3rd edition DMG II and 4e DMG), as I'd always assumed since those are the players I get along with best as a GM. Instead, I'm pretty firmly in the explorer category. Which is kind of the opposite of how I am as a GM; I don't usually have the patience for world detail, and it's been ages since I put together a proper homebrew. But I used to love books like Dinotopia, non-fiction about imaginary places, and gaming can scratch exactly that itch.
Now, I'm finding out about the joys of discovering a character throuh play. Thirteen sessions is a long campaign for me, especially as a player. My record on the stranger side of the screen is 22, and I'd be surprised if, before the Labyrinth Lord game, I'd played in a campaign half that long. My first group had a lot of campaign turnover, and I've yet to establish a long-term group since then. While I enjoy the novelty of short campaigns, I now have a much better grasp on what I'd been missing. Figuring out details about a character (and dwarves in general, in this case) in response to the demands of play is fun, and not really practicle in a short game. Likewise, I'm enjoying the process of negotiating between what I think would be fun and "what my character would do."
Most importantly, I'm starting to understand this thing some call "immersion." I've always been aware of it in general terms, but I'm usually too busy responding to three different player queries at once to really get in to. (I wrote a short story once, but that was based on observing my players more than my own experience.) When I do play, I'm usually equally distracted, whether by books or my own weird conspiracy theories. ("Snakes took our hyperdrive!")
But lately, I really have been getting lost in a fantasy world for a couple of hours a week. Some of it's the length of time I've been playing; I've gotten used to my character and the world and the genral feel of the game. It's also mostly been solo, which might have something to do with it. And a large part of the experience is simply due to the format of online chat. Sure, it's missing that at-the-table social experience, but it's also missing a lot of the distractions of the table, and I'm already pretty well trained to get absorbed into worlds of text.
Still, though it goes contrary to my usual inclination, dissecting the experience isn't as important as the fact that I'm having more fun as a player than I have in years. That's something worth posting about.