Due to the GPU, a PC costing $5300 performs as well as a supercomputer

NVidia is making loud and strong claims; soon graphic processors will surpass the main CPU and will be used for the main part of calculations relegating the others to the not very glorious role of distributors of tasks.
To illustrate this assertion, Belgian scientists have assembled a configuration almost available to the general public containing 4 NVidia video cards, each equipped with two GPU (of Geforce 9800 GX2), and functioning together in Quad SLI.
They succeeded with this configuration costing $5300 to perform better than a supercomputer costing 4,6 million dollars bought in 2005 and containing 512 processors.
For their tests they used software for tomography (medical imagery) and they succeeded in creating an image in 52,2 seconds with the PC that took 67,4 seconds with the large dedicated machine.
Of course, this is only valid under certain particular conditions, however this is a significant step, especially if one compares the costs of the two machines, their power consumption and the costs of maintenance.
To benefit from this on a daily basis, it will not be so simple. Indeed, a war seems to have started between the manufacturers of processors and those of video cards. It seems that today, it will not be easy to get within a reasonable time, unified compilers able to optimise all parts of the machine, CPU and GPU according to their strengths and weaknesses.
However maybe AMD, who has mastered both, or Intel, who are preparing to release powerful graphic solutions into 2009, could make progress on this front.