I actually believe that Button had a good year in 2010. Conversely, I felt that Hamilton drove poorly (by his own standards).
Next year, I think Hamilton will drive better and should be able to increase the gap to Button by using the KERS and movable rear wing more effectively.
1 of the F1 drivers today stated that the movable rear wing is VERY difficult to use. The problem being that when you are entering a corner, having de-pressed the movable rear wing button, the wing does not re-position itself instantaneously. Drivers shall need to be extremely skilled at using the movable rear wing AND KERS buttons at the same time. My belief is that out of all the F1 drivers, Hamilton should gain the most.
In a year's time, if I'm wrong, you can remind me of this.
At this point though, these are merely predictions.