Yes, I have exactly the same problem (and so do numerous other people judging by a web search restricted to the past 7 days.)
Facebook app starts, but returns to the Start screen straight after displaying the news feed. It doesn't actually shut down -if you go to top left of screen (as you would to switch apps) it still shows there.
As far as I can see the only program installed in the past few days is an MS Office Pro 365 automatic update.
Surface Pro (1)
Windows 8.1