Good article. I have to admit I've limited my networking to watching others' productions and social media - but, so far I've gotten surprising opportunities just from those two outlets. Just this morning I booked a short gig because a producer asked me if I knew of anyone available during the 2 weeks she needed, and it turned out I was. Another one had a SM cancel on him on very short notice and sent me a message via Facebook asking me to 'please save him.' He knew I was looking for freelance work because I post my progress in my status updates.
So it does work, people do read it, but the less you sound like you're advertising on your own status updates, the better. Be natural about it.