I grew up reading the Nancy Drew Mysteries by Carolyn Keene, as well as the Files when I was a teen. This series is a step away from the original, wholesome series we grew up with. It is darker, with paranormal twists and turns that are real this time. There is no housekeeper Hannah, her mother died while she was in her senior year (not when she was a child), Bess is new to town, and George is Nancy's boss at the diner she works at. Ned is a former convicted criminal (another twist that shocked me).
The changes are shocking, making for a very different take on an old classic. However, considering the ghost-writers that continued the original series, I view this as yet another ghost-writer's take on the girl detective. It is referenced often thru the series about her being a nuisance in town for going "detective" and all, so her doing detective work isn't new to the town - just more annoying since she's an adult now, not a kid.
Personally, I enjoy watching new takes on old classics - I like to see how they attempt to bring it into the modern world, and what kinds of twists they want to add. There will always be purists that will bash on anything that's not true to the originals - please don't let them color your opinions before you get a chance to watch!