I tried to tag my last years Lotusphere photos, and it worked fine. If you own a GPS capable camera, its easy to combine maps and photos.
Unfortunatly, Google Maps is not available for good old Europe, only UK is available. So tagging your photos from your last trip to Paris will put your pictures right in the middle of nowhere. Zooming out the map you find yourself somewhat east of London in the deep blue sea.
As long as you do not have a GPS capable camera, the easiest way of getting latitudes and longitudes is via Google Maps for the US, or MultiMap for the rest of the world. Then add your taggs to your photo in flickr, and geobloggers will read the tags via your RSS feed. Done.