/ Google Maps vs World
and the new french Geoportail IGN
If you are looking for the best resolution over the World, you should use GOOGLE MAPS, my favorite. If you are lucky in your destination, you will see in a brown background ! The resolution will be astonishing ! Of course you can mix satellite/aerial views with a background map !
If you are not lucky, then the resolution will be only about 30m / pixel (same for Goggle Earth). In that case I suggest using World Wind which will gave you a 15m resolution, just a bit better.
Also in that case, if you are searching a location in France, there is the new Geoportail from the IGN (which announces .5m / pixel on http://www.ign.fr/ but seems to be limited today to a 1:3000 scale). This geoportail is still in infancy and saturated (millions of connexions par hour) and alternatively you can use the more readily accessible french white pages, give an address and a locality then in the coming page any name then select "vue aérienne". Bon voyage !