Blog comments working again
Thanks to a note from Dave Burke I learned that comments had stopped working after the upgrade to CS2008.5. It turns out that the upgrade had turned off the ViewState on all of the post.aspx pages, which I had turned on previously to enable the Invisible CAPTCHA scheme that I was using. I have again turned on the ViewState for the pages that require it. If you notice any quirkiness, please let me know.