If the flash ads don't crash your system, there's a new review of Mask of the Betrayer over at CVG (Computer & Video Games). Handing MotB a very respectable 8.4/10.00, the reviewer, John Walker, says:

There are some pretty significant choices to be made, emphasised further by how you approach your need to gobble up spirits. And for the D&D aficionados, there are plenty more epic feats and spells leaping from the pages of the rulebooks.

If only it could have retained its sense of humour, this would be really good stuff. As it is, it's too po-faced too often, and still contains some of the bugs that bothered the original. However, with a tidied toolset and 25 more hours of story, it's still a solid and well-written expansion to an admirable game.

While a short review, he's got some interesting points but, as said, the flash ads are a killer. Go if you dare!