Using the .NET System.ServiceModel.Syndication classes...
I would like to add a new SyndicationElementExtension to a SyndicationItem that will export the following XML:
<media:thumbnail url="http://www.foo.com/keyframe.jpg" width="75" height="50" time="12:05:01.123" />
Something along the lines of:
syndicationItem.ElementExtensions.Add(new SyndicationElementExtension("thumbnail", "http://video.search.yahoo.com/mrss", ?
How do you create a simple SyndicationElementExtension with a few attributes?
Found the answer here: http://msdn.microsoft.com/en-us/library/bb943475.aspx
Just to simplify for the next guy who comes along trying to figure this out, here's a working example of adding a basic item thumbnail (RSS 2.0 enclosure in this case) along the lines of the documentation:
You can also dump the attributes and just set textual content after the tag name if you want a simple tag, i.e.
<comments>http://my.comments/feed</comments>
.