Yeah, the level design is completely different in V2. The only thing that stayed the same is the time period and general setting.
I'm totally loving it. I'm 19 hours into the campaign, and just started the 8th full mission (yeah, I play slow). All of the features are still there from the original, however I'm seeing a distinct lack of very long distance shots. I think my longest shot so far has been just over 300 yards. It is also about as linear as the first game, which doesn't bother me, as there are usually several ways to approach your targets. And the game looks just glorious - Yeah, I know there are better looking games out there, but V2 does a fine job giving me a real sense of place. I cannot imagine how much work it took to model all of those devastated buildings, and then work them all into the level design, which I think is excellent.
And the new and improved X-Ray Kill Cam just never gets old.