Another optimal post about this area is this. he author said the drawing near to bloggers were not helpful. My gut feeling is that I must approach to the bloggers who might find my social networking App helpful to them. They may be small bloggers.
But when they post anything if there are greater than 20 likes/tweets from their neighborhood. That is a good sign. Your post strengthens my belief. I guess, it may takes 30 60 days to cover the aforementioned strategy for a newly launch app. My another approach is that, advertise in a distinctive iphone App which my App choose to compete with or can solve more challenge than that app.
This will be more focused.