The GPS can be disabled.
About the sensor, I am not an expert by ANY means, but, the TZ10 has a 14MP sensor, but the most you can use is 12mp, whether this means it'll have better 12MP photos than a straight 12MP sensor I don't know, but just putting that out there. At ISO 80 the quality is perfect, here is a 100% crop of ISO 80 during the daytime, at around 5x zoom to boot:
Shutter was 1/400th if you're interested
100% Crop of center of the image:
(This is the banner for a fruit store)