Who reviews the reviewers? The reviewerreviewer... heh.
I think reviewers NEED to be told how their doing as much as anyone.
The worst reviewer (which is what I had to deal with) is the friend giving a review. Telling you how good it's going just to see you reach around 3000 pages and THEN admitting they lied because "you seem so happy when you're writing. I just don't think anyone is going to want to read this."