Nothing is true, Everything is permitted
If you're familiar with Altiar and the first Assassin's Creed then this game will come to you in a snap, if not then the learning curve isn't to bad. Ezio makes for a great protagonist, he's well rounded, is many female's opinions handsom and charming... not to mention that he gets totally bad-ass about half way through the story.
So, how is the story you might ask? Creed II offers you a very in-depth story (yes, it can get more in-depth than the first Assassin's Creed). Tieing the story in with the first one was like a semeless transition, but it also explains enough of the first games plot for new-comers to understand what's going on.
Desmond has a much bigger role in this instalment then in it predecessor, but the main focous is still on the Animus and Ezio; ever wanted to travel to Venice, what about Florence or Rome, well hey now's your virtual chance. With the open world to explore being almost twice the size of the original you deffinatly don't have a limited amount of scenery. The artwork, textures and models that make up the environment in Assassin's Creed II are breath taking at some points, immersing you in the world that is 15th century Italy.
Now then, let's discuss the battle mechanics, Ezio has a few more tricks up his sleeves than Altiar did, and he uses them well. Did you ever wish u could take out two guards at once int he first game, well hey now u can thanks to the invention of the "Duel Hidden Blades"! Ezio is also able to disarm enemies and toss dirt in their faces(among a few other tricks that I don't want to spoil).
All in all I think Assassin's Creed II is an amazing addition to the series, and with Bloodlines on the PSP and in game integration between the 2 if ur lucky enough to own both, ur ride through Italy is 2x as fun