Perhaps this is just another way -- besides the "crisis" tone of the coverage of current events -- that the press is actually (inadvertantly) hurting Obama. Overexposure doesn't do a candidate any favors.
I'm not sure that it's actually the volume of the coverage that annoys voters. It's the hectoring assumption that everyone should be supporting him (unless you're a racist, of course!) -- a tone that comes through all too clearly in a lot of the coverage of him.