OpenSearch results, returned in a standard format (whether that's RSS, RDF, OAI or whatever), would certainly make things easier and less fragile.

To produce a Flitter page at the moment, search results are collected in a number of ways: an XML-based web service for Amazon; text-based web service for Audioscrobbler; RSS for Flickr, and Blogdigger and screen scraping for Feedster.

It must be difficult to fetch results from all the sources listed on the 'add columns' page of A9, so I can see why they want to standardise things.