Interesting note about The Art of War. The direct translation of the title of Sun Tzu's book from in english is "Strategy." Not sure how many people know that, but it definitely makes more sense after reading this book.
The thing I most enjoyed about this novel, was it's structure. If you get a good translation, the prose is not flowery or filled with symbolism. It is like math. One plus One is Two. It is like physics. For every action, there is an equal and opposite reaction. Now, I will concede that this makes for rather boring writing, but you cannot deny it's efficiency and it's brilliance. I have no doubt Sun Tzu was a brilliant man, but the writing won't capture you the way Salinger, Hemingway, Fitzgerald will.
I will agree with Nick, that you don't really 'learn' anything from the book. My largest take-away is simply that, I would have thought the book would be far different than it is. So, now I know the ...TRUTH. It wasn't what I expected, and I think I enjoy being surprised. Anyhow, it is worth a read... but the most important thing to do is to get a good translation. While there will inevitably be lost meaning in translation, there are some books that lose less than others. Make it a point to buy the right copy.