It looks like this poll unearthed a project I had yet to acknowledge!

Clarity is my main theme for GTD improvements in 2010. Whatever enhances clarity would be a candidate for improvement/change.

This includes several items that others have noted including: simplify, more consistent daily reviews, better definition of outcomes and next actions, cleaner distinctions on reference materials, clearer horizons of focus, and better use of the Natural Planning Model.

-Dan