The gameplay was definitely improved, with more melee options and more fluid gameplay overall. Graphics obviously looked a lot better in U3 too.
However, the story was not great. Chloe and Elena were shoehorned in and it was as if Naughty Dog thought of the set pieces first then based the story around them (in fact I think that is what Amy Hennig said in a behind the scenes video).
Multiplayer was obviously loads better in Uncharted 2 too.
I disagree gently. I think the graphics were better in U2. Elena was, at times, a bit too... smooth, and Chloe was a mess. She looked like Nate's grandmother. It all looked too... cartoony. I mean, the graphics were awesome, but not as good as U2. Side by side, U2 looks vibrant, and more realistic. Gameplay was better though, even if I didn't liike Nate's way of going over stuff. The weird, leg up to the side at exactly the same angle when you press X looked really weird.
I kinda prefer U3 multiplayer, but I want beter Co op. Loved the missions where there was a change. Like having to escape those ropes at the start of the Monastary.
It was really good, but U2 had a nearly better everything, discluding the set pieces, and the Talbot fight.