You probably know Jacques Torres from the Food Network - if you're near Soho, you really should check out his shop. Make no mistake, it is indeed a chocolate haven (or should that be heaven?) - the rich smell of chocolate immediately envelops you when you walk in.
The shop sells his truffles, chocolate bars, hot chocolate, pretty much every high end chocolate product you can imagine really. It is expensive, but no more expensive than other high end chocolate stores - that is, truffles are about $46 a pound.
I highly recommend purchasing your high end chocolates (if you must indulge...) at a boutique store like Torres' instead of purchasing Godiva. It's a lot better and fresher, and believe me, you can tell the difference.