Intel is the first company in the world to make processors. Intel's technology is far beyond what VIA technology is.
Intel processors are fast, stable and to an extend they are build to sustain a larger life span. Though the high end processors by Intel delivers very excellent, they do have temperature or say overheating problems.
The architecture of Intels processor incorporates many other features such as MMX, SSE , SSE2, which are very much required for recent games and video and graphics output.
There are number of motherboard manufactured by different vendors based on the intel architecture then that of VIA.
Even AMD processors lack in performance and they have overheating problem too, and they come cheap.
For a normal PC use, say for cyber-cafe like usage, an AMD processor or even a VIA processor will do just fine.
But if u are at running muliple instances of Adobe Softwares and Microsoft Word and other Video editing and Large Game playing then you will have to settle for an Intel Processor only and that what the real difference it makes!!!