My coworker got some from World Market. Wondering how it was? Here's my impressions...
Sight: Marmite looks like rich milk chocolate.
Smell: It smells like a rising yeasty sourdough bread activating (or like a stout yeasty beer).
Taste: You thought the other two together sounded weird? Marmite tastes like French Onion Soup.
Not the worst thing I've ever eaten, possibly the weirdest.