Thanks. One aspect of my question seems to be resolved at least in some searches. A generic location search such as "Hollywood" shows wikipedia information WITH a link to wikipedia tonight, the links were not there before and are still not there for many terms but it's a start. If Google gives proper attribution to all the knowledge they gather then they are following what has become fairly common practice and I'm a whole lot less concerned moving forward. My view is that proper attribution is never optional, even(especially?) for Google.
I wonder how they'll handle knowledge graphs with multiple sources of info, the credit lines could become numerous and add clutter.