I thought this was a fantastic example of someone doing something new in urban fantasy (which is one of my favorite fields to see people doing something new in because I dislike most of the old stuff). Beukes version of magic is innovative and bizarre, but also wholly believable. She clearly put a lot of time and effort into thinking about how the world would change and the universe she created shows that level of care. Zinzi is a great character and easy to feel for, even when you don't feel with.
I feel like most of my good reviews are "nice world building, good characterization, thank you for being innovative in fantasy". Which, I admit, is a bit repetitive, but the exciting thing about an author like Beukes is that she can find her own voice in the world of urban fantasy, adapt it to suit her story and craft a narrative that is both very culturally centered and, without sacrificing its individuality and awareness of it provenance, manages to be universal as well (something that most white male fantasy fails at__�only we let WMF get away with it because the rest of us just suck it up and adapt to the paradigm).
Anyway, Zoo City was awesome and I highly recommend it.