Lauren Bacall died this week, it was all over in the news. When Marjorie Stapp died on June 2, 2014 it was noted in the English Wikipedia only yesterday. Today it is known to Wikidata and, several bits of information where added to the item about Mrs Stapp as well.
Among those statements is her identifier in the IMDB. The IMDB does not know yet about the demise of Mrs Stapp and it is not unlikely that there are more actors and actresses we know about that have died. Providing external sources like the IMDB with an RSS feed of the changes that are made in Wikidata is not hard.
When we share our information in this way, we gain friends. With these new friends we may do friendly things like noting differences between the data that we hold. Equally important, we add a reason why people might maintain the data that is in Wikidata. As our data gains in application, we will grow and diversify our community.