As someone who played the The Witcher for 2 hours and got bored of the game (Mostly hated the controls / the way the game was played) and completed The Witcher 2 I would probably skip it. The only things I thought to myself "Oh I remembered that from TW2" was when you find Phillipa. Not going to spoil anything, I have already finished the main story in about 45 hours doing some minor side quests on the road while pursing the main quest. All in all it is a great game, Only things that bother me are the damn crashes that randomly happen, I've lost some really good loot because of it.