Power View doesn't see Silverlight?

You wanted to present cool Business Intelligence reporting based on Excel 2013 new features. Yet you're stuck as Power View requires Silverlight which apparently you have installed but Excel doesn't see it?

Most probably you have 64bit OS environment and 32bit Silverlight plugin.
Most probably your default browser is other than Internet Explorer which is the only one supported by 64bit Silverlight plugin,

Try to paste Silverlight download link gotten from Excel into IE instead of your favorite browser. If it follows with Silverlight_64.exe download instead of Silverlight.exe then you're qualified for the case.