Previously my home airport, but i've seen it alot this year.
While there's only 1 TSA portal that leads to terminal train, it never takes long to get through the checkpoint. The people are friendly and efficient.
The airport is neatly divided into 4 terminals in a cross-formation and they have made new, clean updates to the food and shopping vendors in the central terminal space.
i love the tidbits of pittsburgh and airport history that hang everywhere, giving travellers and insight to the heart of the airport. It's a shame that non-flyers cannot utilize the shopping as it was designed because the selection of stores is quite good.
For service, rarely do flights stay long on the tarmac and landing and taking off is mostly pain-free. The airport is clean and not desperately crowded.