Some of these responses are hilarious.
The reality is there will be heavy media coverage during one 24 hour news cycle, and then things will die down dramatically. Players in the locker room will largely accept their gay teammate. Most NFL players are under the age of 30, a demographic which widely accepts gays.
The arguments that it's going to be pure hysteria throughout the football organization and a circus with the media are simply nonsensical and overly dramatic. Many of these same arguments were made regarding the repeal of DADT in the military a couple of years ago. Miraculously, our military is just fine, and we'll see the same exact result in the NFL as well.