Unable to post comments (Safari/OS X), Unable to reply (Firefox/OS X)
Using Safari 6.0.2 on OS X 10.8.2 but no Captcha appears at all and clicking "Post" just reloads the page.
I then switched to Firefox (18.0.2, same OS) and was able to post. Later I tried to reply to a post but this time the Captcha for the reply box doesn't appear (although it does still appear for the new comment box). Clicking "Post" on the reply box prompts me to complete the Captcha that never appears.
I do have ad-block active on Safari, but not on Firefox.
Bummer- I'd like to contribute to the thread!