I got a road frame because I just had that wheel built up with the White Industries eccentric hub and I'd rather just get another road frame to use it with. I got exactly a week's worth of riding in between when my parents brought my bikes up and when my old frame broke in half. If I get a new road frame, I can just build it up with all the leftover parts that I stripped off the old one. If I get a track frame, I'd be looking for a new rear wheel, too, and I'm not really in a position financially or motivationally to be making that many new investments all at once right now.
And besides - another year or so I'll have that custom 650c fixie frame.