This is not professional advice. Our ODS was somewhat similar, although he didn't express his knowledge in such a classified manner. He still remembers and can offer up substantial amounts of information about various dinosaurs. It's been about five years since that was his passion (or one of them). Our YDS, who is much more easygoing, can recite and reclassify endless PokeMon information (and will, whether or not anyone is listening).
I personally might worry less about the fact that he does this and look more to how he does with family life, friends, etc. (Allowing for the variation that is normal with gifted kids.) Is this getting in his way, or just something he does?
Keep in mind that there may not be enough material otherwise at school to keep him occupied...
