Verizon Wireless via Engadget:
Verizon Wireless and Motorola are aware of a very small number of DROID X units that have experienced a flickering or banding display. Motorola has resolved the issue and is continuing to ship the phones. Any consumer who experiences a flickering or banding display should contact a Motorola customer support center or Verizon Wireless.
That very small number is approximately 0.1%. For details about the problem have a look at Droid X: Defective Displays.