Philly may be a sports city, but it's not a two-sports-stations city. Especially not when you consider that technically, with overflow on AM, it's now a FIVE sports stations city (when CBS uses both 610 and 1210).
Philly listeners have the "WIP" brand burned into their brains when it comes to sports talk, even with the head start the Fanatic got on WIP-FM. When they want talk they'll tune to 94. When the teams are playing, they'll go where the teams are being broadcast.
The only way some larger cities can support two sports stations is when you have two major league teams in town (like New York with the Yankees and Mets in the spring and Giants and Jets in the fall, or Chicago with the White Sox and Cubs). With only one franchise of each major sport, and CBS controlling the contracts for all of them, there is no hope for a competing sports format.
I dunno, places like Detroit, St. Louis and Minneapolis all seem to have two or more sports stations. I do think that Greater Media should take a run at getting some major PBP on the station though.