It's a pin for St Jude's Children's Hospital.
The St. Jude symbol
St. Jude's children's hospital
It is the logo for St Judes childrens hospital
Fox Sports has an organization called Fox Sports Supports. Each sport they report on is designated an organization to which they support. Fox Sports NFL supports St. Jude Children's Research Hospital, their lapel is their logo.
Supporting Male Breast Cancer awareness
The New England Patriots did send (faux) diamond pins to Season Ticket Holders after Super Bowl XXXVI. I know this because I received one.
They're for St. Jude's (stjudes.org); the two entities have a regular partnership.
Dallas Cowboy pins like that sell in the $4 to $10 range.
There is not a listed meaning for the pins the announcers are wearing today October 19, 2014. The pins usually represent a charity.