Well. I enjoyed this a lot more than I expected. The first episode is powerfully done. The Rape of Cintra involved a great deal of blood, gore and death. Geralt's run in with Princess Renfri has a fantastic section of sword play. Whether it put's GOT's in the shade, that's probably a personal thing. Jennifer's humble beginnings are nicely done.
I feel that because I have read all the books (twice) I could pull all the threads together. I've also played The Witcher 3: Wild Hunt through twice: The game will provide newcomers with little to no guidance at all.
Pulling the threads together becomes more important as the series progresses. It also gets harder the further it progresses. There a number of jumps in time. Both backwards and forwards. If you don't watch with great intent you may become a little confused.
I would always recommend reading the excellent books anyway. The first two; Sword of Destiny and The Last Wish are the basis of series one. Yes there are chunks of the books that are AWOL (to be expected) but it will make more sense.
Episode 8 ended all too quickly but drew things to an acceptable close.
Now for the long wait for season two.