Of course if another photo service has an API, then one application is transferring images and metadata between services.
The Google Web Albums Data API has more information, I'm going to start hunting for people who've implemented their suggested examples:
Some recent additions are documented here. You can even play with them directly from your web browser (click here for my last 25 public uploads in Feed (XML format, I've got them in a Bloglines feed now).
- Include your public photos in your own web page, and allow users to comment on them (and have the comments stored in Picasa Web Albums).
- Write a plugin to manage your albums and photos from a desktop or mobile phone client.
- Create a custom screensaver to display your Picasa Web Albums photos on your computer.
I wonder if it's possible to call these APIs from AppleScript written within Apple's Xcode IDE? If so, it might be possible to do some interesting things almost readily. (Or just use Python?)
I do need to think about this. Heck, it might be possible to suck images directly into iPhoto just by creating a URL-query that creates an RSS feed ...
Today, I do like Picasa, even if Google doesn't understand URLs.