It's tough to say what is going through someone else's mind. I do not know what Trump is doing or why Trump is doing it. I really don't think he wants to be President. But for me I look at this Trump "presidential run" as the positioning or posing of a straw candidate to use for personal financial advantage down the road. He is not a true conservative so therefore he is too liberal for me. The fear is that if Trump runs as an independent he will take some independent and republican votes from the republican candidates and improve the chances for Obama to sneak through as the liberal winner. There should be an "Ignore Trump Campaign" organized by true conservatives. Trump is not conservative and he is more akin to a real estate conman or grifter.
source: http://michellemalkin.com/2011/04/22/donald-trumps-eminent-domain-empire/