schema.org microdata: Do as schema.org says, or as Google says?

Question

When adding microdata to my sites, I use the vocabulary at schema.org.

At the moment, I use http://schema.org/SoftwareApplication to markup software. Since the format is a bit underspecified at schema.org (for instance, what is the difference between url, downloadUrl, and installUrl?), I also had a look at the Google page about this vocabulary.

That made me sad.

It turns out that schema.org and Google use two incompatible versions of the 'same' vocabulary. Some differences:

• fileSize is given in kB according to schema.org, but in bytes according to Google.
• operatingSystem at schema.org is called operatingSystems at Google.
• applicationCategory at schema.org is called softwareApplicationCategory at Google. <rant>...and Google says that the value 'must be one of the supported software application types', but the link to these types is broken.</rant>

Now, to be fair, Google claims that their format is an 'extension' of the schema.org format (but don't you need a new itemtype URL then?), but surely no extension can redefine existing property names (like fileSize).

What should webmasters do about this? It feels like the right thing to do is to follow schema.org. Is there any consensus on this topic?

(I just came up with a hypothesis: Maybe schema.org is the current version, and the obsolete Google pages were written before schema.org was created, and has simply been left untouched (possibly forgotten) since then?)

Underage

Answer 1

I would use schema.org. The high prevelance of the year "2011" on that Google page makes me have a feeling that it is older content that hasn't been updated or removed.

I used schema.org structured data elements on a site I maintain, and all of those elements show up correctly under the "Structured Data" page of Google's Webmaster Tools.

I used the Event, AutomotiveBusiness, NewsArticle, ImageGallery, and CollectionPage schemas.

Danieldaniela

Yes, I also noticed that. Probably the bots of Google are more up-to-date than the documentation. (I'll do some more research before I accept your answer. Tomorrow.) – Underage

I found this: Google currently supports rich snippets for people, events, reviews, products, recipes, and breadcrumb navigation, and you can use the new schema.org markup for these types, just as with our regular markup formats. Because we’re always working to expand our functionality and improve the relevance and presentation of our search results, schema.org contains many new types that Google may use in future applications. So while you can use any of the Schemas on schema.org Google does not currently leverage them for displaying your search results. – Danieldaniela

Answer 2

applicationCategory at schema.org is called softwareApplicationCategory at Google. ...and Google says that the value 'must be one of the supported software application types', but the link to these types is broken.

Have a look at http://www.w3.org/wiki/images/b/b3/Schema.org-SoftwareApplicationsV2.pdf

Thing > Intangible > Enumeration > SoftwareApplicationType 
● GameApplication (action, arcades, etc) 
● EntertainmentApplication (music, sports, TV) 
● BusinessApplication (productivity tool, accounting, finance, tax) 
● MultimediaApplication (audio/video player, consumer photo/video editor) 
● DeveloperApplication (compilers, debuggers) 
● DriverApplication (OS drivers) 
● EducationalApplication 
● HealthApplication 
● TravelApplication 
● FinanceApplication (accounting, finance, tax) 
● SecurityApplication 
● BrowserApplication (web browser, RSS reader, browser add-on/plugin) 
● CommunicationApplication (email , VOIP application) 
● DesktopEnhancementApplication 
● DesignApplication (graphic design, pro audio/video, modeling, CAD/CAM) 
● HomeApplication (decoration, landscaping, DIY) 
● SocialNetworkingApplication 
● UtilitiesApplication (system tools, utilities) 
● ReferenceApplication (books, reference)
● SportsApplication 
● ShoppingApplication 
● MedicalApplication 
● OtherApplication 

Amorphism

Answer 3

Andreas, the unusual properties that you see listed on that "example" page are a combination of schema.org properties and data-vocabulary. Google is aware and hopefully that page will be updated soon. So as eat-sleep-code mentioned, go with schema.org examples. If there are ever any conflicts between the two, always go with schema.org.

Powerless

Thank you for answer, in particular the definite last sentence. – Underage