Re: General assertions in RDF (Do we always have to be specific?)

Thanks for the info.  If I can ask for just a bit more advice... :)

To be more specific, I'm trying to expand on the RSS model used by
tagging sites like del.icio.us. Sample RDF:
http://del.icio.us/rss/wanderingstan These tags, along with the taxo
rss module, allow you to express the topic of a URI.
(http://purl.org/rss/1.0/modules/taxonomy/)

The problem for my project is to figure out what exactly this topic
applies to; just the specific page mentioned? To every page in that
domain? To every page in that domain and any subdomains?

At the moment I'm just applying some best-guess algorithms: "If there
is no filepath in URI, then we're talking about any file from the
domain" or "if a subdomain other than 'www' is in URI, then we're only
talking about pages from that specific subdomain."

My only thought is to add a tag under each <item>,  to get something
like this:
<item rdf:about="http://www.metafilter.com/">
  <title>Metafilter | Community Weblog</title>
  <link>http://www.metafilter.com/</link>
  <gen:apply-to>*.metafilter.com/*</gen:apply-to>
<description>Comunity blog</description>

Is that too big of a hack, or is there a better way? I'm just trying to
make my app "play well with others" for RSS interoperability.

-stan