Both Kodak Z950 and Olympus E-P1 have 12.0 MP resolution sensors but Kodak Z950's sensor is 1/2.3-inch (6.08 x 4.56 mm ) and Olympus E-P1's sensor is Four Thirds (17.3 x 13 mm ).
Since Olympus E-P1'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 Kodak Z950.
Below you can see the Z950 and E-P1 sensor size comparison.
As seen above, Olympus E-P1 has a 8.1x Larger sensor area than Kodak Z950. 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.