Where are all the in-house PR bloggers?

Why are there so few PR bloggers who work client-side? The PR blogosphere is dominated by agency bloggers, freelancers and students. Where is the client’s voice?

There are PR bloggers who work in-house, like Tom Murphy, but they seem under represented. Is it because agency-types, freelancers and students all have a commercial imperative to raise their profile and to demonstrate their understanding to the market, whereas there isn’t that same dynamic for client-side PR pros?

Or am I simply missing the client-side roll call?