Sean Lyndersay has posted about an update to the Simple List Extensions specification. The update fixes some of the issues that were pointed out by members of the RSS community such as the problem pointed out in Phil Ringnalda's post MS Embraces RSS because RSS elements were being reused outside their original context. The cf:listinfo element now has the following structure

<cf:listinfo>
  <cf:sort
     ns="namespace"
     element="element"
     data-type="date|text|number"  
     label="User-readable name for the sort field"
     default="yes|no" />

  <cf:group
     ns="namespace"
     element="element"
     label="User-readable name for the grouping" />

</cf:listinfo>

This is a lot better than the original spec* which instead of naming the element being sorted on using attributes of  the cf:sort element actually included it as a child element instead. The only problem I have with the spec is that I don't see where it states the date format that is expected to be used if the data type is date. I guess this was problematic since different syndication formats use different date formats. RSS 2.0 uses the RFC 822 format, Atom 1.0 uses the RFC 3339 format while Dublin Core [which is what RSS 1.0 dates typically are] uses the format from the W3C Note on Date and Time formats. So an extension element really can't define what the date format will be in the feed it is embedded in since it may be embedded in an RSS or Atom feed.

That is a potential gotcha for implementers of this spec. I think I'll pass at implementing support for the Simple List Extensions spec in RSS Bandit this time around since my plate is full for this release. I'll add it to the list of features that will show up in the following release [tentatively codenamed Jubilee].

* I would have linked to the spec but as usual MSDN has broken permalinks such as http://msdn.microsoft.com/longhorn/understanding/rss/simplefeedextensions/ . Someone really needs to force everybody that works there to read Cool URIs don't change.