There was an interesting Reg article a while back about the storage and network systems used by one of the many VFX houses that worked on Game of Thrones. If someone could dig out the link, it might make an interesting to juxtapose it against Netflick's Virtual Desktop service.
My main takeaway from the older Reg article was that many productions use several VFX houses spread around the globe - either because of the scale of production or because different VFX houses have different strengths - and a lot of data needs to be shared between them.