I didn't read all the posts here, but just thought I'd throw in my 2 cents.
This wasn't my experience at all on the JMT in '12. I felt everyone was happy to be there and very respectful of one another. I passed a lot of people, but when I did I'd either wait for them to yield if the trail was narrow or I would go off the trail and around.
I wasn't trying to break a record or anything, but I enjoyed going fast. I'm a trail runner, and was in the middle of training for 50K races when I did the JMT. So, I felt the need to run, and I did at times. I'm addicted to running. It makes me feel great, it makes my experience better. So for the '13 JMT, I'm going to do a smaller section, but I'm going to camp in a few spots and just go on trail runs around camp. For example, camp at Rae Lakes, run up Glenn Pass, down the other side 5-10 miles and then back to camp @ Rae Lakes.
My base weight with a bear can was around 8lb., but I didn't ask anyone what their "base weight" was. But if anyone commented about how effortlessly I ascended to each pass, I praised my lightweight pack - whether out of modesty, or because I wanted them to be able to better enjoy their hiking experiences without the oppressive/excessive pack weight.