As our photo collections grow into the tens of thousands of photos, Apple is working on ways to make it easier to find particular photos, adding face recognition and geotagging support to iPhoto '09.
In the same way iPhoto '08 enabled users to sort and tag their photos by events, iPhoto '09 makes it possible to search, sort, and tag by faces. Face detection technology, once you've taught the program properly, can identify friends or family members from your larger collection based on their facial features. Once the program believes it has found the person, it will ask you to confirm and tag the photo with their name. The tagging process is similar to tagging photos in Facebook. Clicking a top-level Faces collection in the sidebar shows all the people you've identified.
Unfortunately, face tags are not exported with photos, although it may be possible to assign a keyword to a person easily, and export that. It's also worth noting that the face recognition technology is unique to iPhoto and isn't more generally available in Mac OS X for other applications, which is a shame.
Additionally, with Places, users can sort and tag by the location the photograph was taken. Cameras with geotagging capabilities mark your photos with the longitude and latitude of the location they were taken. iPhoto interprets this information and correlates the spot to a Place in its database, showing pins on a map generated from Google Maps. If you don't have geotagging capabilities, you can instead manually tag photos or groups of photos with locations listed in iPhoto's location database.
Other than the iPhone, only one consumer-level camera, the Nikon Coolpix P6000, makes it trivial to match GPS coordinates with photos. More are on the way, but as Glenn Fleishman explained in an Ars Technica article, it's not a trivial problem due to how quickly cameras are turned on and off, leaving insufficient time to get a satellite lock.
iPhoto '09 also now includes useful Facebook and Flickr syncing capabilities. You can click a button to sync your photos to your Facebook or Flickr accounts, complete with name (for Facebook) and location (for Flickr) tags. You can even perform the reverse function, sending photos from online collections to your iPhoto library with tags in place.
Additional changes include more advanced slideshow customization and new themes that can all be synced to your iPhone and iPod touch. Finally, the new version includes enhanced Travel Book options including more themes, better printing, and geotagged maps.
iPhoto '09 is part of iLife '09, which will ship in late January 2009 for $79 or $99 for a family pack. Also available then will be the Mac Box Set for $169, which includes iLife '09, iWork '09, and Mac OS X 10.5 Leopard. New Macs will continue to ship with iLife for free. If you purchase a new machine between 06-Jan-09 and 31-Mar-09 that does not include iLife '09, you can upgrade it for $9.95 through Apple's iLife Up-to-Date program.