I have included pictures with my city and PT side by side. The bags were over-stuffed so that they would stand up to their full height.
The third picture makes the part-time look much wider than the city and the city much taller than the part-time, which is entirely caused by the camera angle. I couldn't make it come out any better. Refer to the first two for a true size comparison.
I would say that the PT is just about 1.5 inches wider than the city and the city is 0.5 inch taller than the PT
Julie...which bags are you comparing? PT and City? The differences I detect are: PT is a bit wider, a bit shorter (top to bottom), has a seam down the middle in the front and the back (which I prefer because it breaks up all that blank space, make sense?), and has a longer strap (24" i think vs. 18/19" on city?) which allows for messenger style wear.
For those of you entertaining the idea of a PT, my local Neiman's is also getting it in black, white and blue india, some time soon (the SA couldn't give me an exact date).
I checked with AR, they are not getting the PT in either Camel or Blue India, here's the list of colors they are stocking: Noir, Truffle, Sapin, Blue Roi and Greige.