SoftwareApplication and schema.org extension mechanism

I was watching a video on using microdata and schema.org for Google
Rich Snippets for software applications [1]. At first I was surprised
that something for software applications wasn't already included in
schema.org, but on reading a webmaster support page [2] it states that
it is a Google extension of schema.org of the CreativeWork type. The
suggestion is to use http://schema.org/SoftwareApplication as the
itemtype. It seems from the schema.org Extension Mechanism page [3]
that extending CreativeWork would more correctly be:
http://schema.org/CreativeWork/SoftwareApplication

Am I not understanding the schema.org extension mechanism? Or can the
schema.org partners just extend schema.org as they please without
using the extension mechanism? Or maybe this is a candidate for
expanding the schema.org vocabulary, so rather than putting the
extended forms of the URLs out there in the wild the choice was to
just starting off with what the URLs would be if they were a part of
schema.org? If so, is there other public documentation of where the
schema for software applications is being hashed out? It seems that
there are some properties like license name which could help support
discovery of open source software.

Also the suggestion for the softwareApplicationCategory property is to
use one of the supported software application types listed on a web
page [4]. The recently updated JobPosting type [5] also appears to
suggest that the value of the occupationalCategory should use an
outside taxonomy [6].  Are there other examples in schema.org proper
where one should choose from a list of types like this? It seems as if
this is another kind of extension mechanism that schema.org has to
manage with some of the vocabulary maintenance falling to
organizations outside of schema.org. Is this likely to be a recurring
pattern? How can content authors and tool creators best keep up with
cases where the suggestion is made to use a value from an outside list
for a particular property?

Jason Ronallo

[1] http://www.youtube.com/watch?v=Yc8CQoWrsE0&feature=BFa&list=SP3107CD6C86454FE3&lf=list_related
[2] http://support.google.com/webmasters/bin/answer.py?hl=en&answer=1645432
[3] http://www.schema.org/docs/extension.html
[4] http://support.google.com/webmasters/bin/answer.py?hl=en&answer=1645527
[5] http://www.schema.org/JobPosting
[6] http://www.onetcenter.org/taxonomy.html

Received on Tuesday, 20 December 2011 22:27:19 UTC