It probably wouldn't be _cheap_, but yes, it is convenient. I know quite a few residents who commute from Philly every day. Of course, they usually have to be there at around 6:30am, so traffic really isn't a problem...
I don't know much about the bus system, but there is a train station essentially across the street from the school that connects to Philly. A ticket is about $3 (one way). I'm not sure if you could get a discounted commuter rate. It's also an easy drive by car- if you don't go during rush hour. (Yeah, yeah... I know.) I can make it into Philly from Cherry Hill in about twenty minutes without traffic. It's $3 or $2.70 (E-Z Pass) to go over the bridge, but you only have to pay one way, of course.
Hope this helps!
Paige