I didn't get to play much yet, but I enjoyed what I did very much. The first mission with the house on the beach was impressive. That's an excellent level.
In the case of Hitman 2, I'm glad they didn't try to reinvent the wheel since the last game's mechanics were great. New locations and to take out people was honestly all that I needed, so I'm good. I agree that fans of the series should enjoy this one.
I played a bit of the Sniper add-on too and I'm excited about the possibility of DLC in the future for that mode. I haven't tried it in co-op yet, but the potential for that and campaign levels is exciting. There's a lot that can be done with this game down the line.
My only gripe isn't really that big of a deal but it's a little disappointing. I was a big fan of those CGI sequences before and after missions in the last game, but those have been replaced with art stills for the most part. Those were so well done that I hate that they're gone, but I understand that sacrifices had to be made with them no longer at Square Enix.