Both Fujifilm X30 and Sony W230 have 12.0 MP resolution sensors but Fujifilm X30's sensor is 2/3-inch (8.8 x 6.6 mm ) and Sony W230's sensor is 1/2.3-inch (6.17 x 4.55 mm ).
Since Fujifilm X30'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 Sony W230.
Below you can see the X30 and W230 sensor size comparison.
As seen above, Fujifilm X30 has a 2.1x Larger sensor area than Sony W230. 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.