This is my favorite place to get coffee in Pittsburgh by quite a large margin.
The location (which is in the process of moving about 50 feet) is in the heart of the strip, and is a great place to kick off an adventure on a weekend morning in the strip. The baristas are extremely knowledgeable about the drinks and show tremendous skill in making them. Always willing to share knowledge about the different types of coffee and best methods of preparation/consumption. Especially considering they serve "traditional" beverages (as opposed to what Starbucks has led us to believe..), the customer education is paramount and they take it very seriously.
If I could offer some advice, don't add any milk or sugar to this coffee. The baristas are very good at understanding each customer's beverage preferences (more/less milk, flavor profiles, etc.) and tailoring drinks to their needs.
It's a great place to go to get educated on coffee or just enjoy a great beverage. 21st Street is the best in all of the city.