We are still sorting through the nearly 100 responses from readers on the question, but the following one offers a good primer of recent coverage in the blogosphere:

As a lifelong sports fan and football watcher, I have to admit I've lost much interest in football since the issue of brain injury and concussions went mainstream last year. GT_FOOTBALL-HEAD_120329And as the father of young children, I have seriously reconsidered whether I would allow them to play football at any level.

Is it conceivable that football could disappear? Tyler Cowen and Kevin Grier recently laid out the case. They make a persuasive one, as hard as it is to fathom. However, counter to that argument, football is very different than tobacco or seatbelts – unlike football, those two harms lack one major feature: a massively involved fan base. There has never been a huge TV audience or stadiums full of rabid fans cheering on smokers or drivers putting on seatbelts. I don't think you can discount this factor – the thirst for sanctioned violence in sport runs deep in our culture and, perhaps, human nature itself. I can imagine football diminishing in popularity rather than it disappearing altogether.

Regarding your question of whether brain injury is worse now than before, the answer is yes and no. Brain fractures and resulting death were more frequent before advances in helmet technology, but ironically this has led to more brain injury. Jonah Lehrer wrote an interesting piece about this.

(Photo: London Crawford #2 of the Arkansas Razorbacks lands on his head after catching a pass against the Louisiana-Monroe Warhawks at War Memorial Stadium on September 6, 2008 in Little Rock, Arkansas. The Razorbacks defeated the Warhawks 28-27. By Wesley Hitt/Getty Images)