I tried Jetpack yesterday. Specifically, the Jetpack Comment. It works great, though seems a bit difficult to configure how to make it work functionally. I think maybe the readme should say that it should have
<?php comment_form(); ?> in comments.php (I was having trouble with custom comment form). :)
Anyway, when I try to validate my page using the w3's semantic extractor, it returns in failure. It says,
"The entity name must immediately follow the '&' in the entity reference."
I checked my source code and suspect that this is the culprit causing it, which came from Jetpack:
comm_par = (comm_par_el && comm_par_el.value) ? comm_par_el.value : '',
Not sure if this is a suggestion, a bug report or a feature request... please correct me if I put this topic in the wrong place. :)