I'm reading Fooled by Randomness and really like it. The Black Swan I couldn't finish because it kind of rambled. Not sure if he had a better editor for Fooled by Randomness or what.
Fooled by randomness seemed to me a little bit less rambling as well and a little bit more straight to the point. But I liked the more essayistic style of Black Swan as well (well, I studied literature, so i think I am just used to these kinds of writing).
