In a continuing trend to have users add location metadata to content uploaded to Google servers (following YouTube), Google’s Picasa Web Albums has now gained the ability to let you georeference photos from inside the browser, using Google Maps. Here is the announcement on the Official Google Blog.

How does this newfound ability compare to the georeferencing via Google Earth available for a while now in the standalone version of Picasa (for Windows and Linux), or the georeferencing already available on Flickr and Google’s own Panoramio?

First, here is how it works in Picasa Web Albums (henceforth “PWA”): Everything is focused on simplicity. For any photo in your online account (1GB comes free), there is now an “Add location” link, which leads to an Ajax-ish Google Maps popup on the page itself that first forces you to search for a place and then lets you tweak the exact location.

Georeference a number of photos in an album, like this one of Stockholm photos I have laying around, and the album itself can be viewed on a page in a layout that looks remarkably much like Google My Maps, down to the “View in Google Earth” link — which gets many kudos for its seamless integration. From this page, you can perform further tweaks simply by dragging the photos on the map. It couldn’t be any easier.

Stockholm

But there is one significant omission when compared to all the other services: Upload a photo that already has coordinate data in its EXIF metadata, as I did here, and it is not automatically mapped — you still have to georeference it manually.

If instead you first import the same photo to the standalone Picasa application, it does recognize the EXIF coordinate data, and will show you its location if you choose the menu item “Tools > Geotag > View in Google Earth”. If you then sign on to PWA from within Picasa, and upload such a photo to PWA, as I did here, PWA does automatically georeference it. (This makes Picasa far more geo-savvy than Apple’s iPhoto, Aperture, or in fact any other standalone PC photo editing tool I am aware of.)

[Update 2007-06-29: There is a preference setting that turns on the use of EXIF location data in PWA, but it is off by default. For security reasons? Importing from standalone Picasa overrides this setting, however.

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Unlike PWA, both Panoramio and Flickr use EXIF coordinate data [by default] during a browser-based upload, and will map the photos for you automatically: Here is the photo uploaded to Panoramio, and here it is uploaded to Flickr.

By the way, Panoramio’s georeferencing “tool” is almost identical to the one PWA has just gained. This leads to some interesting questions as to how/if these two services will be integrated. There is significant overlap between the two services, though Panoramio photos are almost entirely comprised of postcard-style landscape shots. One solution might be that in the future, if users georeference a photo in PWA, Google asks if it might be suitable for inclusion in the Google Earth layer of descriptive landscape shots. And as for visualization… I think PWA’s new My Maps look is the way forward.

The main advantage that both Panoramio and PWA have over Flickr is the seamlessness of their integration with Google Earth — it is just a link, as it should be. In Flickr, viewing in Google Earth still requires some hacking, though if Flickr’s Dan Catt has anything to do about it (and he does) there soon will be built-in KML links for Flickr images. Until then, Panoramio is the only service that both recognizes EXIF coordinate data upon upload AND outputs seamlessly to Google Earth, with the added ego-boosting bonus of finding your photos published to a default layer in Google Earth. [PWA can be made to use EXIF data via the settings.] (BTW, Panoramio yesterday announced that another 200,000 photos were added to the Google Earth default layer, bringing the total to 1.2 million.)