I confirmed to myself this past weekend that there is a definite issue with my D2X and the D2X of others with the cameras ability to acquire and track a moving target (bird), be it a full 1/2 frame subject or something smaller, at medium to long distance.. I have discussed this with others well versed at this type of shooting who have shot both the D2H and now the X and have been told that they are experiencing the same issues. This was tested using both a 300 AFSII and a 500 AFSII. Acquisition (lock) was very difficult if not impossible at times and focus yield was substantially lower than 30%. Prior experience with the D2H yielded substantially higher yields, in the 70-80% range. This occurs at medium to long target distance in any focus mode and in any contrast situation. It appears to be worse with targets moving towards or away, the the yield is better with targets moving parallel to the camera. At close range....ranges of less than 40 feet, there appears to be no issue at all, at least with my particular camera. I have contacted Nikon (someone of service prominence was contacted directly) and advised them of the issue and have been told that it will be looked into immediately. As soon as I hear anything official, I'll post the information.