Oh BOY! Amazing!
It worked on the first go. There are several things that I ended messing up in my theme though.
1) I tried adding comments count just below the post title, near the {Block:text} part. So, in my theme, the blog title fonts changed and intead of persisting on top, it persisted on bottom. (With persistence I mean staying at the same spot no matter the scrolling.)
2) Similarly, my Spyndex theme (?) has this progression - text, tumblr notes, tweet. I put my FB comments blog right on top of everything, and somehow, all of the above blocks became left aligned instead of center. Where do I change all of these themes?