Actually people/joggers/ipod lovers have the right of way. You have to move for them. Trail etiquette, sorry. This topic comes up every so often and always seems to turn ugly.

And no, I don't stick to the right side of the trail. I take whatever line looks the best, and I just pull off to the side when there's a pedestrian, equestrian, or uphill cyclist who has the right of way. I move if I'm riding slow as crap and there's someone coming up behind me too. Better to inconvenience myself for a whole 2 seconds than to cause a problem that might eventually cause access issues with the trails.