I finished the 2010 playoffs 51-31 or 62.2% to the good against the point spread with a simple all-overdog strategy.
For the past 3 years, I have followed what I call my Gibbs-Gipp system:
http://economics.stanford.edu/files/Theses/Theses_2007/Gibbs2007.pdf
and have called 55.7% of all playoff games correctly against the point spread.
And, over three years of picking NCAA March madness matches, I won 53.9% against the spread.