I think it will be interesting to see the details of this project. Most of the current offerings do not have anywhere near the technical sophistication that FB can bring, and especially as they iterate I think they will leave every other cryptocurrency in the dust.
It will be centralized. Under Facebooks control. And even if some kind of realy hinest and pro-users TOS would be possible, I don't trust that my password is safe in Facebook imagine my money. This is another thing for "dumb people".