I think people on HN tend to forget that most people dont care about the technical requirements etc. The reason people use facebook because its usage is clear a

I think people on HN tend to forget that most people dont care about the technical requirements etc. The reason people use facebook because its usage is clear and defined for what its build. You go on Facebook to check in with your friends, see photos, chat/message. You just dont do it with a blog. It's like saying you could use paper towels as toilet paper. There is probably some overlap in functionality, but people clearly associate types of products with their specific use case