It's a fine book and, as others have pointed out, might seem like just common sense. The trick is that Sun Tzu managed to quantify things so simply and succinctly.
The team developing Shogun 2 Total War is actually coding The Art of War into the AI. If you read The Art of War, it really does seem like it was written by a programmer. It's full of lots of practical "If this..., then..." advice.
Since we're talking about classics, my all time favorite is Strategy by Sir Basil Liddell-Hart. Whatever you think about the controversies surrounding him, his explanation of the strategies of indirect approach and interior lines was very enlightening and made me a better gamer.