DW and I love the books (BTW - a new one has just been released in the UK, and is being released in the US on April 20 - The Double Comfort Safari Club).
When the TV series started, DW at first refused to watch. She said that she wanted to keep her own ideas of how the people looked and acted, and that no actors could do justice to the different roles. But I watched it and got hooked - and got DW to watch, too. All of the actors are just perfect, and the TV series gives you a much better feel for the general atmosphere: the way people talk, the way they dress, the street scenes - and the wonderful music.
Definitely two thumbs up. I hope season 2 starts soon!