If you think about it for a second, we still don't have that great mobile-only social app yet. The mobile versions of FB etc. won't cut it if the next 5-10 year

If you think about it for a second, we still don't have that great mobile-only social app yet. The mobile versions of FB etc. won't cut it if the next 5-10 years are going to be all about mobile. IMO, FB is extending its vertical with a mobile-only social app AKA the "FB OS."