mxyzplk said:OK, this is an important point. "Open" isn't a meaningless marketing term, it's a very specific attribute of a license. Here's the Wikipedia definition of open content: http://en.wikipedia.org/wiki/Open_license.
Point of order. If Wikipoedia said the sky was blue it is still best to check a window.
The definition you cite is the very restrictive, viral definition that the zealots push.
Viral is *NOT* a requirement for openness. Transparency to the system ( whether that's through visible and documented APIs or access and ability to resuse of the source material/code ) is what matters. Anyone could implement NFS. It was an open standard. Anyone Could build a PDF tool. It's published and royalty free. They just don't meet some NARROW views as to what means open. The debate about the harmfulness of viral is here nor there for this discussion.