<< a few prions never scared me away from some tasty cow >>
Actually, if prions are one of the causative agents of BSE (Bovine Spongiform Encephalopathy) or VCJD, then cooking will not inactivate them. Mouse brains cooked at 160C for 24 hours did not fully inactivate them.
<< cow = good eating cow brains= bad >>
I agree, eating the muscle of the cow is very tasty and is at a much lower risk. But the warning on the brain tissue also extends to the spinal cord and I believe the GI tract.
In a nutshell-- I will continue to eat steak (minimal risk) but will probably stop eating any product that has been make by mechanically separation methods, i.e. hotdogs.