Or.... whoa, not yet, lol! SEPTA's former Reading line from Ewing, NJ to Philadelphia is in no danger of become a bike trail thanks to its popularity with yearly ridership on the West Trenton Line holding steady at roughly 3.5 million passengers. As for the bicycles - two bicycles are permitted on each car in passenger service both weekdays and weekends, with an exception of some rush hour trains inbound to the city in the morning and outbound in the afternoon. More information about SEPTA's bike policy can be found here.
Two rapid transit lines, PATCO and PATH, take commuters to Philadelphia and New York, respectively. Metro North locomotives and rolling stock often show up on NJ Transit northern lines and SEPTA terminates routes in Trenton and West Trenton.