Perhaps, most notably, is the introduction of built-in support for online services Facebook and Flickr in iPhoto '09. We think the annoucement pretty much trumps yesterday's release of Picasa for Mac.
The Facebook and Flickr integration is an exciting new addition to the product that will make iPhoto the dynamic photo sharing application it should be. Now, users who upgrade can automatically send their photos to Facebook and Flickr within iPhoto. As soon as you post new photos of friends to Facebook, notifications are also immediately sent to your tagged friends.
With Flickr, when you share your new photos, locations are shown on Flickr photo maps. Given that the new iPhoto also has three additional much needed features - Face Detection, Face Recognition, and Places - tagging faces, names, and places in iPhoto for online sharing turns into an almost completely automated process.