I'm fairly new to freelancing full-time (it's been about 9 months), and I had been doing it on the side for a few years, but I've consistently made over $2k for the past few months. It comes from a combination of 'content writing' for sites such as DS and LTK mainly, and the rest is from a variety of private clients.
I have a steady gig as a newsletter editor and pretty consistent freelance work with a local firm, so that helps me to know what to expect. Any magazine or other freelance assignments beyond that are just icing on the cake and padding for my portfolio. I'm still a long way from my goal though, want to be making at least $4k a month