This is the best place to get coffee in Pittsburgh. There are other places that sell incredible coffee- Espresso a Mano, Prestogeorge Coffee & Tea, La Prima Espresso, and Marty's Market come to mind.
However- if you want your coffee shop to be supremely comfortable for doing some work or meandering around the internet- look no further. I've never had Wi-Fi issue unlike many places. This is the best place to unwind no matter what the weather's like outside and enjoy some coffee while getting some work done. Their chai tea latte is the best I've had in the city. Some places can't get that right.
The atmosphere is great, it's a beautiful old town home with multiple fireplaces, eclectic furniture, and bright colors everywhere. The staff are very friendly. It's a great place to go and I'm sure you'll keep coming back.