When Flickr added built-in mapping of photos, many rejoiced. However, it can be tedious to go through hundreds/thousands of photos and dropping them on a map. The User Interface for the Flickr Maps is really great - however, with this many photos, it would just take forever.
In addition, your photos are only geotagged in Flickr - and therefore not easily usable outside the service. The better way to geotag your photos is to actually write the Geo data to the EXIF of the photo. Then the metadata is carried around with the photo itself (until you pass it through some mean, metadata chomping machine like Photoshop).
The way I geotag my photos is to first get the coordinates of photos:
- Carry around a GPS and store the tracks as GPX files - then you can mesh the GPS with the photos using WWMX (Windows), GPSPhotoLinker (Mac), or various scripts in Linux (fend for yourself, but check the geowankers mail archive)
- Mark GPS Waypoints - or lookup addresses of locations and use MultiMap to get the latitude/longitude of these points
After I've either meshed up my coordinates, or have a list of locations, I fire up iView Media Pro, or iPhoto, and use my Applescript scripts in addition to ExifTool to actually write the GPS metadata. Because photo editing applications (like the aforementioned Photoshop) are usually very mean and don't restore geo-metadata on edit and save, I suggest you edit all your photos first, and apply the geo Exif as the last step before uploading.
Now that you're going to upload your photos, you first need to make sure Flickr uses these geotags for actual mapping. Enable Flickr to read your Geo EXIF tags. If you already have uploaded photos with geo-coordinates in the Exif data, Flickr will add these to the map (after a short wait - queueing and all).