jQuery load() and Facebook Comments
Facebook API's annoy me. It's not clear where to get information so I feel your pain.
With that being said, it seems that you have raw XFBML uninitialized in the lightbox. It looks like you need to reparse the data after it is loaded.
<fb:comments migrated="1" publish_feed="true" width="600" numposts="10" href="http://frank.is/blog/2011/05/26/google-apps-on-iphone-connection-to-the-server-failed/" xid="VQ4yhN59hJmmSXq_post73"></fb:comments>You can try manually calling parse after you load the XFBML into the lightbox:
FB.XFBML.parse();or to target a component to optimize the load:
FB.XFBML.parse(document.getElementById('fbComments'));