Aarrrghh!!! for all its usefulness and genius of design, I specially like the Auth part, the Flickr API does not provide a straight forward method to get all the comments made on a particular photo.
The only hack I could think up was to aggregate the Recent Comments RSS, parse it (they do not send the image ID as a tag either) and cache the results in a DB to be shown with appropriate photos… the downside besides being very crude method is that I cannot get comments on my non-public pictures 
Anyone got a better idea?
You might wanna ask the folks on yws-flickr. Maybe Stewart will notice and if there are enough requests for such a method, it’ll be added.
I saw that the feature has been requested often enough at Flickr API Discuss group and yws-flickr mailing list… have started lurking at both the places