What is definitely true, is that nobody I know feels anything positive about facebook, at all. It is seen simply as a sinister, addictive[1] necessary evil. This is the case regardless of technical expertise. They continue to use it purely because of inertia and lock in. Yet they are not interested in twitter either.
Much like smoking, many people get into it as teenagers because everyone's doing it, now in their 20s they've realised that it sucks but they can't stop.
There is definitely a market for a social network thats simpler, but still full-featured like facebook, but above all one that's less "evil." One that's vocally dedicated to your privacy, and whose every move doesn't seem so machiavellianly calculated to keep you coming back, to the point where you begin to feel like you're living in a dystopian future world.
I realise that's just a long way of saying "less profitable" or even "not profitable," but there we are.
[1] The main slang term for facebook amongst it's younger users in the UK is "facecrack." It has been called that for years.