Flickr launches People Tagging. Yes, just like Facebook.

Flickr has launched a new feature that has for some time played an integral role in photo sharing on Facebook.

The tagging feature called “photos” works similarly to Facebook in that you can tag friends on Flickr. To add someone to a photo, you can either type in the member’s name, much like you’d add a tag, or you can add a boundary on the photo, as with a note.

People can opt in and out of the tagging, and unlike on Facebook, once you have opted out of a photo, no one can head back in after the fact and add you back in. Your nights out are now safe from the friend-arazzi.

Flickr of course has more than one major hurdle to jump over, namely that you need to be in someones Flickr contact list to be tagged in an image. This will lead to an expansion of the average size of a Flickr contact list, and of course to the overall Flickr userbase.

But is it enough to have the photos be less constrained by the Facebook privacy options, to make the new Flickr people tagging a hit? Perhaps it will be very popular among the Flickr elite. But while Facebook continues to grow as it does now, the new Flickr capabilities will do little to stem the tide of Facebook as the photo hosting and tagging platform of choice for most of the world.

Flickr should have done this years ago, literally.

As with Facebook, once you are tagged in an image, your activity list will be updated. The more you think about it, the less original this feature really is, but it is nice indeed to see Yahoo do just about anything.

For the ever curmudgeon, you can opt out of being tagged in any photos. For the senior or party animal in your life, that might be just the ticket. Do you plan on using Flickr people tagging over Facebook?

Zee contributed to this post.