Sorry Rifleman gotta disagree...
I also live in the burbs about 20 min outside of center city and I purposely have been paying extra attention to the crime. Its not just north Philly, West and Southwest Philly anymore.
Its all over Kensington, Port Richmond/Fishtown, Northwest including Germantown and even people being attacked in Fairmount Park (Valley Green), Northeast Philly (guy was shot dead in his car in Mayfair this morning also), South Philly including South St, Society Hill (recent muggings), and even a few sprinkled cases in Olde City.....the popular and trendy hangout for night life.
Im 30 now and have visited a ton of places in Center City and Im telling you I dont feel safe there at night anymore. I trust my G26 with my life now in the RARE occasions I go into the city anymore.