Certainly there will be some extra rare items as well as items that have to be completed from several parts. A good example here is a special dwarven sword called sihil. Before you can use it, you'll have to complete some side quests in order to get all its parts, and then find a runesmith capable of re-forging them into a truly unique weapon. You will not find items falling out from opponent's bodies like in some other action RPGs, so don't expect getting a kick-ass sword after killing some giant rats.
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As has already been said, the majority of quests can be completed in different ways. I'd like to stress once again that quest design is really something extremely important for us. As most of the player's decisions influence the game's ending, we have to prepare various paths and solutions for many different situations that might come up during the adventure. We want to confront players with some serious moral choices and reflect them in the actual gameplay.
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One of the most crucial changes is abandoning the turn-based combat. Now, all the action takes place in real time (we do have an active pause option), and this definitely makes the gameplay more dynamic. Thanks to this, combat looks more spectacular and better suits the witcher's style, which is based on extraordinary speed and agility​