I don't read a lot of fantasy but this is one of my favourite series. Every time I pick up the latest instalment, I'm struck again by the incredible imagination & world building of this author. She has turned vamps, ponies, crows, wolves & intuits into real "people" you come to care about deeply.
All of the books work as pure entertainment. But if you care to ponder them on a deeper level, you'll find an allegory for the world we live in. Societal issues such as racism, prejudice, xenophobia, war & family drama are all dealt with, albeit in a slightly furrier way.
There are many reviews out there already so all I'll say is I highly recommend this complex, multi-layered story. And don't even think of starting here. This is one you where you need to start at the beginning (Written in Red).