NEW YORK ( TheStreet) -- Demographic data tells us that a considerable number of people who read TheStreet also listen to sports radio. That makes it safe to assume (I think) that you have heard of Jim Rome and Scott Ferrall.Unlike other parts of your life, however, the sports radio habit tends to have very little impact on your investment thought processes and decisions. While you might take other everyday experiences under advisement when thinking about stocks, sports radio likely never enters as a factor. That makes sense. It's small potatoes. Consider some perspective. CBS ( CBS) owns all-sports WFAN in New York City, the nation's first and biggest sports radio station. In 2011, WFAN brought in $40.5 million dollars in advertising revenue, making it the ninth largest biller in radio across formats. In its most recent annual report, CBS reported total revenue of more than $14.2 billion. Last quarter, it generated nearly $3.5 billion in sales. That makes WFAN a big fish in the small pond of radio and an even bigger fish in the even smaller pond of sports radio. Even so, "The Fan" accounted for less than 0.3% of CBS's total revenue. No wonder why Mike Francesa can fall asleep on the air and get away with it. Nobody at corporate likely pays much attention. I wonder if this dynamic could begin to change. Disney ( DIS)-owned ESPN operates a longstanding radio network alongside its other media properties, particularly television and online. News Corp's ( NWSA) Fox does the same. In recent months, NBCUniversal (majority owner is Comcast ( CMCSA) and CBS have put similar plans into motion. There's more still to come from both companies. In network radio, ESPN Radio, Fox Sports Radio and NBC Sports Radio presently exist. CBS Sports Radio begins 24/7 programming on Jan. 2, 2013. Of course, all four have considerable local, regional and national presences in sports television as well as online. As a contender to ESPN and Fox, CBS might be the most interesting case. Much of its lineup will clear the nation's top 50 radio markets thanks to CBS's properties and a partnership with Cumulus Media ( CMLS).