Will this work with FB integrated comments?

It appears that Facebook’s Comments Box loads by Javascript, so the comments never actually reach your blog’s server. It would be technically impossible for Thank Me Later to work with Facebook Comments Box, since the plugin doesn’t have access to commenters’ email addresses or comments (unless I’m missing something obvious).

I will be releasing a small update tomorrow which adds support for Disqus, which perhaps you will be interested in switching to if you wish to use Thank Me Later.