FujiFilm S2800HD has a 14.0MP 1/2.3-inch (6.17 x 4.55 mm ) sized CCD sensor . On the other hand, Panasonic LX5 has a 10.0MP 1/1.63-inch (8.07 x 5.56 mm ) sized CCD sensor and features Venus Engine FHD processor.
Below you can see the S2800HD and LX5 sensor size comparison.
As seen above, Panasonic LX5 has a 1.6x Larger sensor area than FujiFilm S2800HD. 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.