See, this is something I've never understood. For me, the cleric has always been the big member of his/her church. The paladin is LG first, part of a church second - their dedication is to being the classic chivalrious knight, and while that does include religion, that's not all it's about.
I can see an anti-paladin, a paragon of evil, if you will, yes, but a neutral or unaligned paladin? At least speaking for me personally, that goes against everything paladins are supposed to be about. Paladins are about passion, about being a part of a driving force dedicated to Good to rid the world of evil (Or good, for the anti-paladin ;p). Mind you, that doesn't mean they're ALL MARTIAL ALL THE TIME - the paladin has Diplomacy as a skill for a reason.