I do like the Kyle's art in the foreword but was not an enormous fan of the cartoony art later in the book. I have nothing against the artist but I ust don't think it helped the book. I agree that the sandpoint character art wasn't great. While I did like the art in the main section more (paticularly liked the picture of elf ranger) I still didn't think it really suits pathfinder.
I've always preferred more realistic art for D&D, your imagination is already stretched greatly by the game it is nice to have a realistic looking frame of reference. With the more cartoony look I feel like it just requires more suspension of disbelief. After all that isn't a picture of a person it is clearly a cartoon rendering of them. With the more realistic art this isn't a problem. Just my opinion, but I will be glad to have kyle do the art work for the foreword. Just would prefer that style of art to be a bit less prevelent in the rest of pathfinder which from the sound of James Jacobs it will be.