yeah I do track. I'm a distance runner too.

I gained 12 lbs since november (cross country season) from lifting and eating more, and my bodyfat has stayed the same. I think I lost a little BF because I was a bit overtrained in the fall. I was a skinny little b*tch (5'11 140lbs). Anyway, I think I got a little slower.... I can't keep a 7:00 pace for my long runs anymore.

For track, there is no reason you should be doing more than 35 miles/week. We do lots lots lots of interval training, and so far I haven't noticed an effect on the muscle I gained over the winter. Just keep eating enough, that's what I try to do. It's really hard to fit enough lifting in during the week, but I try to get each muscle group in at least once a week after an easy day at track or something.