Nikon S1200pj has a 14.0MP 1/2.3" (6.17 x 4.55 mm ) sized CCD sensor . On the other hand, Kodak Astro Zoom AZ651 has a 21.0MP 1/2.3" (6.17 x 4.55 mm ) sized CMOS sensor .
Kodak Astro Zoom AZ651's sensor provides 7MP more than Nikon S1200pj'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 S1200pj and Astro Zoom AZ651 sensor size comparison.
Nikon S1200pj and Kodak Astro Zoom AZ651 have sensor sizes so they will provide same level of control over the depth of field when used with same focal length and aperture. On the other hand, since Nikon S1200pj has 44% larger pixel area compared to Kodak Astro Zoom AZ651, it has potential to collect more light on pixel level hence have less noise in low light / High ISO images.