I had this in Hawaii. It smells like fart and tastes like fermented cake. Definitely an acquired taste.
Wikipedia says it best:
The edible flesh emits a distinctive odor, strong and penetrating even when the husk is intact. Some people regard the durian as fragrant; others find the aroma overpowering and offensive. The smell evokes reactions from deep appreciation to intense disgust, and has been described variously as almonds, rotten onions, turpentine and gym socks. The odour has led to the fruit's banishment from certain hotels and public transportation in southeast Asia.