Typo

It's not uncommon for Typo users to hit the submit button on a comment, and then hit it again. Because the comment box isn't wiped prior to submitting the comment, this often results in the same comment being posted twice.

A fairly trivial solution would be to store the comment text in a Javascript variable, and then refuse any subsequent submits where the text was the same. Sure it could be circumvented, but his would definitely reduce the number of double commits.