None of my friends annoy me in the real world, so there is no reason why they would annoy me on facebook. So I really can't relate to people who talk about annoying depressing status updates or whatever. Clearly if you're news feed is feel of that shit then you have lot's of randomers or friends of friends or whatever. If you don't then surely the issue is the company you keep rather than the medium they are using to express their views.
Facebook has been responsible for so many good times for me that I will say that facebook is a fantastic tool for bringing people together. I would never write a letter to someone and I rarely bother emailing people, but I keep in touch with people from all over the world that I have met at different times, the number of people I regularly catch up with and see what their up to, I would never have the time to email.
Facebook is brilliant if used correctly. It has it's place.
I think that most of the time people who bitch about it are just trying to be a little bit anti-establishment, people always like to hate mainstream shit, but usually this causes them to lose sight of the great aspects of a product or service. One other thing to the original poster..
You have 521 friends on Facebook. Perhaps THAT is your problem.