I received a call from a certain DO school in FL that my application was complete in July and up for review. I hadn't heard anything by end of August so emailed and mid October they informed me that my MCAT (taken in July) wasn't on file. Every other DO school had received it and I had gotten interviews already and even acceptances, so someone on their end dropped the ball. No big deal because I'm very happy with the way it worked out, but still it was sort of annoying that things got screwed up by probably someone the equivalent of a student worker.
So the way I see it, it can't hurt to follow up because some schools are not known for their organizational skills.