I've heard mixed messages as to where to sit on the saddle - scoot back, scoot forward - scooting back seems to help me the most (from article 4 below, this seems to be related to height - short, scoot back; tall, scoot forward). The thing I'm working on now is keeping my heart rate steady (or at least not blasting it into the stratosphere) when climbing. Easier said than done, and I doubt it will ever stay completely steady, but the goal is to get better at keeping it within range.

Here are some links:

http://www.bicycling.com/article/0,6...1304-1,00.html

http://www.bicycling.com/article/0,6...-183-1,00.html

http://www.bicycling.com/article/0,6...8581-1,00.html

http://www.bicycling.com/article/0,6...4758-1,00.html