They certainly must have employed a good writer who knows how to write dialog; however, it's unusual to see even well-written dialog that blends into the game so well. It very often feels a bit tacked-on; unnecessarily wordy. Gaming is an interactive, dynamic medium, so big stretches of wordy dialog feel as unnatural to it as twenty-minute cut-scenes. Riddick did both dialog and cut-scenes in such a way that they don't interrupt the flow of the game — gameplay is first, everything else is subordinate to it and supports it. Yet the story manages to get told.

I'm not saying it's the end-all be-all of gaming (there are plenty of things it doesn't do well, or at all) but in this particular respect it has few peers.