You can add locations, captions and sync your changes to your photos in Picasa and Picasa Web Albums. You need to turn ON "Web Sync" in Picasa to sync changes to Web Albums. Open "Picasa" on your computer and turn ON the "Sync to Web" switch located at the right of an album. Click the arrow next to the "Upload" button and select "Enable Sync" option. Now you can sync your changes to photos in Picasa and Picasa Web Albums.