cutoff attempts to comment through wp-comments-post.php if Comments Box enabled for the post type of the comment post ID
Merge pull request #421 from niallkennedy/pre-comment

provide a comments closed equivalent for POSTs to wp-comments-post.php
move social plugin field choices into key-based matching for faster lookups
Merge pull request #422 from niallkennedy/social-plugin-choices

compare social plugin choices by key, not value