I'm a licensed driver in NJ and received a speeding ticket while
driving in Pennsylvania,(4 points). I understand that the PennDOT
motor vehicle code states that drivers licensed in PA will have a
relative point penalty assessed to their PA driving record. Are these
points transferable to a licensed NJ driver's record under the Compact
Law?

I think the points obtained in PA will be transferred to NJ. Each
state has some kind of agreement with neigboring states to inform
incidents of traffic violations by an out of state vehicle. I had an
incident in WV with my PA plates and the ticket mentioned about
informing PA about the incident so that corresponding points may be
assessed in PA. Of course I paid the unfair fine to avoid all the
hassels.

It might be a little too late but yes you do get 2 points, every out
of state speeding ticket equals 2 points.  If you lived in PA and had
a tickete in NJ then it wouldn't show up but stupid jersey has to be
different from every other state.  Here's the link for the info:

http://www.state.nj.us/mvc/cit_violations/d_vp_pnf.html#IC