You can view the latest published version of the specification @ http://www.w3.org/TR/discovery-api/.
All work on this specification happens in the W3C Device APIs Working Group. If you would like to be involved in the process of creating this specification then you can subscribe to the W3C Device APIs mailing list and mail in your comments.
Opera have released a prototype of the Network Service Discovery API (according to the 4th October 2012 draft version of the specification). Head over to the Opera Developer Relations blog post to download this build for Mac, Windows and/or Linux and for further details on getting the provided demos up and running.
All feedback is welcome!
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