These videos look much blockier on my Macbook Pro (8600M GT / 2.5 GHz) than they do on my PC laptop. The Macbook has better specs than my PC laptop in every respect. I am comparing the same videos back to back and playing them on the same 24" external monitor.
I am new to OS X, so please be patient. If there is more information about my settings that I need to provide I would be happy to do so.