David Icke is a complete nut job! He's completely bonkers... He once was a famous english football player. One day he decided that he was the son of God! He actually went on 'Terry Wogan' (at the time the most popular English Chat show) and said as much, the audience was not impressed at all. After a while out of the spotlight, he decided that he wasn't the son of God, no, he now believes that the world is dominated by a bunch of repitilians that have taken human form. Hmmm... yes David... that's much more sensible!
If there's a conspiracy or crazy fad theory out there - he's backing it... He ranks right up there with Uri Gellar in my book.