This book was *fun* ... but at the same time, felt like McDermid literally copy+pasted the original text into a word processor and just did some find-and-replace to change things just slightly. This read like Austen with some additional social media angles (and the much-maligned text-speak) but what really needed to be updated were some plot issues. 
 For instance: (spoiler tagged even though these are all plot elements of the original novel) (view spoiler)[ 
 - why does nobody find it odd that two grown men -- practicing lawyers -- would be so immediately attracted to a girl they know full well is 17? 
 - this may be passable in a Pretty Little Liars/Rosewood/creeper manner, if Cat wasn't also a sheltered, homeschooled, naive innocent who's never been out of her little town before in her life, making her act far younger than 17 
 - Bella and James get engaged right away, despite not even dating first? And Cat's (and everyone's) response is just to be happy for them? And not wondering, why don't they go on a date first? Or move in? 
 - The weird focus on getting married and family money may make some sense in a Gossip Girl sort of way, maybe, but the Allens' and Bella's focus on family wealth and making a good marriage read as more Regency era than 21st century 
 (hide spoiler)] 
 And on top of that, and this is probably an element of the not-very-popular original novel, but the plot is all over the place. In pre-publication interviews, this book was described as being reimagined as a teen suspense thriller (and hence McDermid's involvement) but the "suspense" elements (are the Tilneys really VAMPIRES??) is never a real threat, as even Cat knows she's being silly to suspect that.