Canon ELPH 150 IS has a 20.0MP 1/2.3'
(6.17 x 4.55 mm ) sized CCD sensor and features Digic 4+ processor. On the other hand, Olympus 8010 has a 13.0MP 1/2.3-inch
(6.08 x 4.56 mm ) sized CCD sensor and features TruePic III processor.
Canon ELPH 150 IS's sensor provides 7MP more than Olympus 8010's sensor, which gives a significant advantage in real life. You can print your images larger or crop more freely.
On the other hand, please keep in mind that Max sensor resolution is not the only determinant of resolving power. Factors such as the optical elements, low pass filter, pixel size and sensor technology also affects the final resolution of the captured image.
Below you can see the ELPH 150 IS and 8010 sensor size comparison.
Canon ELPH 150 IS and Olympus 8010 have almost the same sensor size, so neither of them has any significant advantage over the other in terms of providing control over depth of field when used with the same focal length and aperture.