We work with geotagged images a lot in Picasa. This gives instant spatial context to where our photos were taken, which makes them much more valuable then as just oblique images alone. We can a) geotag images manually (see here for how), or b) geotag images automatically with a GPS camera (e.g. our Sony Camera). When we geotag them automatically, it often works great, but sometimes does not. This first video shows us how to download images that have an incorrect geotag, and how to update those in Picassa. It also highlights some pictures that were correctly geotagged, and some that we have to geotag manually.
Once we have geotagged images in the stand-alone version of Picassa, we frequently want to share them with others. With Picassa, we do this by creating web-albums. This video shows us how to do just that (warning... nearly 15 minutes):
See also Picasa Help for more information.