Duuuude!! I just had one of the most amazing experiences with AC2 last night! One of the side assassination missions in Tuscany has you tailing a guy to lead you to the guild leader. So I followed him until he eventually found and was talking to the leader, with I think two other guards with him. Couldn't get close to him on the street as he got suspicious when I was near, and I was hoping to poison one of the guards in the hope he could be taken out for me. So I climbed up to the top of the building and thought ok, I'll jump down, assassinate him and then switch to the sword and take out the rest. So I swoop down for the kill and Ezio takes out the target and the man I was tailing with a double blade kill!
I forgot you could do that! And then I immediately switched to the sword and as one of the two guards swings at me I immediately counter it with an instant kill. I was getting ready for the second guard's attack when he just dropped his sword and ran away!
The whole thing was just so seemless and fluid that it must have scared the crap out of him!
Also went through the Assassin's Tomb in Tuscany too. Loved it, I mucked up the first encounter with guards, but the rest of the time was all stealth kills. I can't wait to explore the rest.
Good news is that a sequel is bound to be in the works. Over 6 million copies have been sold. And for a game based in Renaissance Italy, as a sequel to a mixed-reception game, that's pretty impressive IMO.