archaven: In my EYES, Witcher 2 is actually DIABLO LITE. They can certainly learn more from Diablo 3 in that aspect.
Whereas in my eyes... lemme analyze it a bit:
a) Inventory: TW2 is weight based, D2 is grid-based.
b) Crafting: TW2 has it, D2 don't.
c) Socketing: Both have it, D2 has a much more complex system (Horadric cube etc.)
d) Loot: TW2 is minimalist, has hand-placed items. D2 has randomly generated items.
e) Story: TW2 has a fully-developed story with interweaving plots, D2 has relatively minimal story
f) Potion: TW2 has potion-making and meditation-based drinking, D2 has in-battle potion chugging.
g) Combat: TW2 is based on KB + mouse with player deciding when to block/dodge with OTS cam, D2 is top-down and mainly mouse with F1 to F8.
h) Character attributes: TW2 doesn't have STR, DEX, VIT, energy stats that player can decide, D2 has that.
i) Skill trees: TW2 has alchemy / sword / signs, D2 characters have 3 trees too but they generally are confined to a mold, i.e. sorceress can't really be developed as a
j) Enemies: TW2 has few monster types and relatively small number of enemies compared to hoards of enemies
h) Abilities/perks: TW2 has some, D2 doesn't.
i) Quest rewards: TW2 has orens and items (except for a single one), D2 gives you levels, imbuing, skills points etc.
Not so sure what you mean by DIABLO LITE.