Data Visualisations: Art or useful?

Recently with a plethora of datasets becoming made freely available there has been a surge in data visualisations as illustrated below. These are a particular favourite of WIRED magazine. I know look amazing but what actual use are they? Are they designed purely as Art, then great. Would I use one to illustrate a point for one of my projects? Probably not. Don't get me wrong I think they look great but what is their real value?

Thoughts on these visualisations welcome......

Airspace: Europe from ItoWorld on Vimeo.