It's truly a powerful and successful adaptation of the book and I highly recommend it.
I loved the new mythology of the creatures and the fact that there isn't much blood or teenager stories in it. I watched the series first then the book and to be honest it was unnecessarily long and in this case I'm happy with the speed of the series and that it's not gonna go further than 3 seasons. Packed and fast enough without any boring redundant stuff of the books.
The other point of the series is the more inclusive approach of the British adaptation to characters comparing to the very "white" approach of the book. They make the appreance of the characters more diverse at least, which made it more interesting for the non-white fans.
The casting and colour palette of the scenes and costumes are fantastic. Matthew Goode fits perfectly into the vampire character and Palmer is acceptable as Diana, btw.