RSS broke out of its news-and-weblog-tracking ghetto this week when Amazon.com expanded its range of syndicated content feeds. The online retailer published a new list of about 200 ready-made RSS feeds, each showing the top-selling items for a particular subcategory or search term.
The functionality is not new; the RSS feeds have been available to anyone who could work out how to create them since last summer. Paul Bausch explained how it works at the time, but you had to be comfortable working with the technical details to take advantage of it. Doing it the hard way does give you more choices: here for example is an RSS feed of the bestselling books on web services that I just created (you may need to 'view source' to see the feed in your browser). If you don't have an RSS reader to hand, here is the feed converted to HTML. If I wanted to be really clever, I could change the "f=http://xml.amazon.com/xsl/xml-rss091.xsl" parameter at the end of the Amazon URL, and substitute my own XSL stylesheet to convert the information into other formats (which would be a neat demonstration of the virtues of transformation).
But most people can't be bothered with all this messing about with URIs and XSL (Eric Raymond rightly calls this sort of thing An Open-Source Horror Story). They just want a link they can click on, and that's why Amazon has gone to the trouble of publishing the 200-or-so most popular RSS selections. By doing so, the company has stepped beyond the realms of what's technically feasible and ventured into the much more populist arena of giving people a finished product. So even though the more techically astute may have wondered what all the fuss was about, internetnews.com was right to highlight the move in its news story, Amazon.com Joins RSS Bandwagon.
The other thing that's interesting is that this is the first mainstream example of a retailer using RSS to disseminate its product catalog. Every item in those feeds carries a price, with a direct link to a page offering the product for sale. That's qualitatively different from the mainstream uses of RSS that have been seen in the past, almost all of them devoted to disseminating information and signally lacking a revenue model. Amazon's embracing of this new medium reaching out to deliver filtered excerpts from its catalog to a fast-growing marketplace of RSS readers is characteristically original in its thinking. Where Amazon leads, other online retailers would be well advised to follow.
UPDATE [added March 7th]: David Galbraith points out that Amazon's RSS feeds show up the format's current weaknesses by lumping price along with other bits of metadata into the RSS <description> field. His posting has attracted a flurry of comments from industry luminaries including Dave Winer, Phillip Hallam-Baker and Amazon's own web services evangelist, Jeff Barr. It's one of those threads in blogland where you can actually see the collective wisdom advancing as the interaction continues (a good example of how Blogs Can Be Infectious?). Jeff rightly points out, as I noted above, that anyone is free to transform the data into a more meaningful feed in response to which Les Orchard has already set up an alternative XSL stylesheet to create a demo feed. As I was saying before, Only transform.