The Pingback feature was disabled for all myblog.arts blogs, due to security concerns. This feature can be used by external users to co-opt WordPress blogs in attacks on other websites. There may be an update to WordPress in the future which will enable us to reactivate Pingbacks.
What is a Pingback? Here’s a brief explanation from the WordPress.org site:
The best way to think about pingbacks is as remote comments:
Person A posts something on his blog.
Person B posts on her own blog, linking to Person A’s post. This automatically sends a pingback to Person A when both have pingback enabled blogs.
Person A’s blog receives the pingback, then automatically goes to Person B’s post to confirm that the pingback did, in fact, originate there.