Google are buying into it to share with NASA and various universities. The revolutionary technology is no doubt the start of a whole new era of computing progress. Perhaps this is the start of the Singularity.
They claim that when it runs it is the coldest thing known to Humankind. Perhaps the coldest place in the entire universe. If it is then we are sure to get some attention from our universal neighbours. Along the same lines as figuring out anti gravity which is probably the next step in this quickly escalating process.
The next question appears to be what can we do with such a machine now that we have one. The answer is that it is perfectly suited to tasks such as facial recognition which is probably the first thing it will be used for. Google claim that it will help them fight spam too. No doubt it will also be useful for undertaking certain climate modelling tasks and in the hunt for life hosting planets with the reams of data the have been collected already needing many years to process with conventional computing resources.
One thing is for sure, For certain tasks this new system is the fastest thing we have built yet.