Think of this as the obligatory "I consider myself a runner because..." post.
When I am actually running (i.e. when I'm not taking a 10 year hiatus from running), I've never not considered myself a runner. It's not because I enter races (even though I do), and not because I can run longer distances (which I do), not because I place overall, or even in my age group (because I don't). It's not because I train a ridiculous amount to not place in my age group (which I think is true, but that could be my lazy side speaking), or the speedwork, and drills I do.
It's because, despite the bitching I do about speedwork, running in heat and humidity, running when it's -25 with the windchill, and runs over 20 k, and despite the complaining I do about waking up at stupid o'clock for long runs, and the fact that I can't go out as late, or as often because of running, there is nothing I'd rather do. Even though I bitch and complain and don't place in my age group when I race, I still love to do it. Because sometimes I have one of those perfect runs where the weather is fantastic, and I feel fantastic, and the run is over before I know it, and it's awesomet. Because even though I don't place in my age group, I am getting PBs/PRs, which is just as good (although does not get me free socks). Because I've met some fantastic people are just starting to run, and some that have been running for ages. Because when it comes down to it, I enjoy it.
And that's why I'm a runner