Our Blackboard isn't buggy, has never crashed or crashed my computer, and it has been updated regularly, so I have no idea what you're talking about. Pretty much every class I've been in (minus some studios) have required Blackboard. You HAVE to check the email attached to it, because profs send out assignments, announcement, etc. with it and not checking your attached email will probably get you an F. It's a university requirement, I'm going to use it. But requiring the use of Facebook on top of that is stupid and pointless and I would not want to do that. My personal life has nothing to do with my academic life and unless I'm actually friends with a professor, I'm not going to add them on Facebook, for the same reason I don't want to add my employers.
I guess you could do without Blackboard, but why? It's a good resource. I can email everyone in my class if I don't actually know their emails. We have forum discussions. I have an easy place to get syllabi and assignments. There are resources there. I can turn in assignments and take quizzes. You can't do half of these things on Facebook at all and the other half, you'd have to be in a group or be friends with people, which is something I am not comfortable with and students shouldn't be forced to do it.
Some art shows are promoted through Facebook, but that's a networking tool that the galleries and the students who are in those shows have decided to do and I find that acceptable. It's just another way to advertise shows and doesn't cost anything. Requiring students to have a Facebook to organize a show, though, just sounds dumb. It's a social networking site. Requiring its use in a class just because a lot of people use it makes it unfair for those who do not wish to use it.