Money buys a surprisingly strong sense of loyalty -- your hired goons will do what they can to battle pesky guards, or even attempt to take on your target if you're otherwise occupied. It's a useful advantage in the face of overwhelming odds and does much to prevent public battles from dragging on for too long. Aside from loyalty, your money also secures a level of patience usually reserved for a shopping spouse. Your assassination assistants have no qualms about idling while you stop mid-mission because you simply must have those shoes.
Purchasing minor aesthetic upgrades is a silly example (purchasing a vial of poison is a much better one!), but it effectively reveals how Ubisoft has targeted and improved upon the first game's greatest strengths. The rich visuals still draw you into a believable, bustling city, but something as simple as a shop -- an additional point of interaction -- further helps sell the illusion. The increased interactivity within the world can be social, allowing you to utilize vagrants and prostitutes to your advantage, or more personal, like the somewhat inexplicable health potions in your pocket (accessible via the d-pad).
Your movement has also seen subtle improvement, with Ezio significantly speeding up his climb if you hold a straight course. He feels more nimble than Altair, even though the basic controls stick close to the model established in Assassin's Creed. One aspect that has seen less notable change is the combat, which still leans a bit too heavily on split-second counters. A new set of weapons (including ones claimed from fallen enemies) are a good addition, but in the aftermath of Batman: Arkham Asylum, the process of luring out attacks can feel a bit rote.
Though our limited time with the TGS demo made it impossible to gauge just how much creativity had gone into the overall mission structure of Assassin's Creed 2, it did provide a worthwhile glimpse at the expansion of "role-playing" elements. Providing more ways to interact with an already compelling world (be it through social interaction or ill-timed shoe shopping) brings the game closer to its goal of making you feel like a hidden blade in the crowd.