Both Nikon S30 and Ricoh GXR P10 28-300mm have 10.0 MP resolution sensors but Nikon S30's sensor is 1/3-inch (4.8 x 3.6 mm ) and Ricoh GXR P10 28-300mm's sensor is 1/2.3-inch (6.17 x 4.55 mm ).
Since Ricoh GXR P10 28-300mm's has a larger sensor area with the same resolution, this means that it also has a larger pixel area hence better light collecting capacity for a given aperture compared to Nikon S30.
Below you can see the S30 and GXR P10 28-300mm F3.5-5.6 VC sensor size comparison.
As seen above, Ricoh GXR P10 28-300mm has a 1.6x Larger sensor area than Nikon S30. Larger sensors give photographer more control on the depth of field and blurry background compared to smaller sensor when shot in same focal length and aperture.