Oh, and number one reason broadcaster use "tank " cameras, we already bought them! The low end is $10K and going up to $60k (digital cinema camera go higher), then add the cost of the lens, these people bought their camera maybe last week or 6 years ago, why spend more money and throw away something you may have not even paid off yet.
AVCHD has much more potential than HDV, Panasonic already has a version of in their newer cameras, but at 50Mbps. HDV's long-GOP or nasty for high motion shots and nastier to edit.
Plenty of shows do us smaller cameras as a back up, ever see "Dirty Jobs", they run two shoulder mount cams, but the producer jumps in with a Sony Z1U, a $4k HDV camera.
But it really is all about image quality. Color reproduction, control, resolution, image processing, dynamic range, compression.