The app could be sort of a replacement for the Camera.app (that is the vision). What it can do is

a) Take a picture and store in you photo library on iphone (as iPhone's Camera.app does)

b) Plus : Uploads the pics to Flickr

a) and b) happen with just one click. Check out the video at http://iflickr.googlecode.com/files/iflickr.mov

I would definitely add tagging in the next release. Another possibility is adding automatic geotagging to the pictures by using phone's cell tower information.

--pradeepta