I beat Uncharted 2 for the first time! (On easy, admittedly; I just wanted to experience the story rather than risk frustration)
I thought it was a definite improvement over the first game, with a much wider variety of locations. The voice acting was outstanding and it felt like an interactive action movie.
Thankfully the shoot out at the monastery was the most frustrating part of the game. The final battle with Lazarevic felt a lot more video gamey than what I remember of the final boss of Uncharted 1, but it was much more memorable for it.
My only complaints are that the platforming could be a little finicky at times, and while it wasn't to the extent of the first game, there were times where it was unclear how I was supposed to get to where I needed to go. (At least one part sticks out where I had to go through an open window in a courtyard; the game gave me no indication of how to do that)