Hi Bob,
As you are a librarian let me tell you what we do as Wikimedia Italia.
In the last two years, we have been growing strong relationships with libraries and librarians.
We have developed a collaboration with the National Library of Florence, and last year we created a property in Wikidata that
linked the terms of the Italian Thesaurus with Wikipedia articles (via Wikidata).
That was really cool for them, as they we're seeking a way to crosswalk the thesaurus with other thesauri:
as Wikidata has become a super-authority control (it has many properties that are identifiers for persons), it can be also a super-thesaurus, as a hub for national ones.
Moreover, we are experimenting with a local Wikibase, populating it with bibliographic metadata [1]:
it is a complex project, as we need to find a model for describing resources and books at different levels (at least "work" - "edition").
We started it because in the past we had a very good feedback from the EAGLE project [2],
a joint European project in which Wikimedia Italia is subcontractor.
They are developing a new standardised database for epigraphic metadatahere (there have been several database scattered across universitiies, and also several metadata standards): we suggested the creation of a Wikibase, for that, and after several months we can say the project is a success and the epigraphic community was stunned with the flexibility and power of Wikibase. Eventually, some of these data will populate Wikidata.
We also did recently a conference at the National Library of Florence in which we explained Wikipedia, Wikisource and Wikidata, the projects we think suits the most for libraries. ou can have a look at the November GLAM report (and previous ones too)[3].
Of course, there is a growing interest about Wikidata, and we hope many librarians will start contributing.
I just see one, big, limit in all this:
for being *truly* effective, a librarian should know his way around Wikidata: how to propose properties, chow to discuss with other users, how to run a bot (or how to bribe a guy with a bot). Wikidata is a brand new project with a brand new community, it is not "defined" at all and it is inherently complex. For example, I was one of the proponents of the WikiProjects Books [4], but this stuff is difficult and in the end I quit (did not have time to folow properly). At the same time, you'd need professional librarians (and good ones) to find a way to create the right properties, decide which and how many items create for each book, and balance all this with the fact that you need to serve Wikimedia projects (so you need a Wikidata items to be connected to Wikipedia, Wikisource, Wikiquote, Commons, etc.).
Hope this helps :-)