I agree! I live in Wilkins Township near Churchill Road and have seen a lot more people on bikes (also walking and running) recently. The area is a really nice place for cyclists – commuting to Pittsburgh and Monroeville is pretty easy, more rural roads in Westmoreland County are within reach, Frick and Boyce Parks are close and offer excellent mountain biking, and most houses have a two car garages that will easily house many, many bikes.
There are myriad feasible routes in and out of the various municipalities east of Pittsburgh, so I think bike commuting traffic is dispersed. Biking and driving around the area I see a lot of people in a lot of different places (also at a lot of different times of the day). Quite a few individuals also ride recreationally after work and on weekends (and when the weather is decent large numbers of people mountain bike at Boyce Park).