I think this is a good idea, but the problem I see is how to make it immediately available for comments. Most letters are seen in the top 20 once enough people have already hit them. This would not automatically be in this category. This would have to go into a separate area meant specifically for helping out letters by commenters, similar to 15 minutes of fame. Like the positive letters with the happy faces, many are never commented on so this would have to be earmarked specifically to be out there just for that purpose.