Mind Games - S4-E16
Revealing mistake: When Jen and Jack are having coffee at the coffee shop, Jen walks outside and turns to bang on the outside window of the store to get Jack's attention. When she hits the window, you can tell it isn't a real window made of glass. It's obviously some sort of plastic, as it flexes too easily and moves too much to be a real store window. This was probably done to make the window safer for the actors during this scene.
Answer: It's the same apartment Joey had in NYC. Comparing it to the beginning of the Finale; you can tell it's exactly the same location, furnishings, Plasma TV etc. Apparently Chris was only living with her at HER apartment, and now Pacey has taken his place at the end. I guess this implies Pacey successfully started his own restaurant business in NYC as he had dreamed, to be with Joey.