I'm wondering if this is unique to system. Here is the test: 1. Load up any movie that is ripped to your hard drive - i.e. DIVX etc. 2. While playing, lift the laptop in the air a few inches and let it drop gently to your lap. You can also try to firmly "tap" the bottom/front/right of the MBP (where the hard drive is) for the same result. Does the movie freeze? Stutter? Mine does. I'm led to believe that either my particular HD is overtly-sensitive, improperly installed or defective, or else that the HD is generally too exposed in the Unibody design. I wouldn't find this problematic except that movies freeze and stutter with often the slightest movement while the notebook is on my lap. Please post your results.