Before anyone says the opposite, aside from politics and Hockey, there isn't a true Philly-Pittsburgh rivalry...
I haven't noticed much either. Since I have moved to the area the main comment I notice is that folks from SE Pennsylvania always comment on how Pittsburghers talk. I've even heard folks originally from Pittsburgh commenting on their own speech when they move to this part of the state.
There does seem to be a perception among Steelers fans that the Eagles are snooty or snobby. To my surprise, the Steelers seem to be slightly more popular here, even though we are 65 miles from Philadelphia but 240 miles from Pittsburgh. On the other hand, Phillies fans far outnumber Pirates here.