Facebook Comment Social Plugin - Get Comment Count on Nodes and Views
This might be late to answer, but do checkout Social Stats module.

This is a statistics module. It provides data from various social media sites. The data which is saved per node. It includes data from:

Facebook : likes count, shares count, comments count &amp; total count.
Twitter : tweets count.
LinkedIn : share count.
Google Plus : plus one count, share count &amp; total count
Total Share Count : total across all available social networks


It has an view integration. So, it would serve your purpose exactly.
P.S - I am the author and maintainer of the module. If you find any issues please feel free to report using the issue queue, and I'll be glad to help.