It's me who's framed them specifically as a Facebook replacement in this post, and certainly what they're doing is a reaction to Facebook's issues. But if you

It's me who's framed them specifically as a Facebook replacement in this post, and certainly what they're doing is a reaction to Facebook's issues. But if you read their project description, it doesn't sound like what they're building only duplicates Facebook's functionality. They're talking about providing software to give you your own portable persistent data vault, that you can selectively allow other people & services to access, while keeping the ability to remove their access at any time. That's pretty cool, and it has the potential for a lot more uses than what Facebook is doing.