This is weird, it started happening just now. I can use the FBComment box to comment and on my next page load I see the wp comment counter being refreshed correctly, however, the post doesn't show up in the wp comment list. And in the source code neither.
what shows up in the source code is the line "" repeated as many times as comments supposed to appear there.
For example: if there are 15 fb comments, the wp counter shows "15 comments", in the wp admin panel i see the new comments coming in (as if they were imported), they actually enter the wp comments database, but in the source code i'll only get the line "" repeated 15 times
Maybe this happened after I closed the comments/trackbacks of one certain post for a while, and when I opened again it was like this. Or maybe thats just when I really noticed the problem, but the plugin has been working fine up to now.