I personally find that the PlayStation controller is the smartest one yet. Maybe a tad small, but then, I have fairly big hands. I do totally agree that the L2 and R2 shoulder buttons on the PS3 controller are bad, though. They should have left them alone! :(
I also found the ol' N64 controller surprisingly intuitive! When I first saw it, I thought 'what is that thing?', but I got used to it very quickly.