Tomb of the Giants is one of the best areas in the game. Come at me.
Seriously though, I thoroughly enjoyed the Tomb, but it seems like the DS and GB community consensus is that it's one of the worst areas in the game. I'll agree that some of the areas and enemies post-Crystal Caves don't stack up to the rest of the game, but just watching Vinny play through the Tomb convinced me to get Dark Souls and play the hell out of it.
Why do you not love the Tomb? Love the Tomb.