I just came across this while looking for something else, but I gave it a quick try.  Here is what I think so far...

1. I like how the rollback bar steps through the features and the new features are highlighted / selected.
2. It seems like a lot of wasted space in the task pane for just comments.  I would like to see it used for more information:
   1. Perhaps show all custom properties, segregated by general and configuration specific
   2. Show the feature properties information (e.g. Created by, date, & modified date, also configurations the feature is used in)
3. I would like to see an option to show the sketch in the graphics view (if hidden), and another option to show the sketch's dimensions (as if the feature was double clicked).  These two check boxes could be at the top of the Part Reviewer task pane.
4. When I am done with the Part Reviewer, I'd like the features to collapse back to the state I had them in before running the review.  In a long feature tree, not collapsing them back can make a big difference.  I know users can RMB in the feature manager and select "Collapse Items", but since you guys are automating things, it makes sense that this would be automated as well.