We are attempting the West Buttress on Denali in 2010! If anyone has any pointers I am all ears. I can carry 50-60 lbs (it does slow me down) but am capable of carrying 45lbs for many days without suffering much. I keep my Jandd Golith pack in my car and hike with it up hills during my lunch break. I vary the pack weight from 30-60lbs.
I also bring a heavy pack with me when we do trips with slower people. This summer I threw 40lbs in my pack when we hiked Mt Washington with my parents. (It kept me from going to fast and it was great training!)
Anyway, enjoy! -