Libraries do collaborative collection development, through consortia and increasingly via direct institution-to-institution arrangements. Reference and instruction are collaborative endeavors—look at any social-networking service with lots of librarians and you'll see on-the-spot crowdsourced reference responses.
Perhaps this collaboration instinct will help libraries respond to the challenge of domain expertise for data curation. Do I need to know cheminformatics, or do I just need to buy a cheminformaticist conference potations until I secure her business card?
Formalizing expertise-sharing arrangements strikes me as rather difficult. Nobody wants to be the person everybody across the country calls with questions about ChemML; when would there be time to get any work done? Still, I would have thought that collaborative collection development had too many moving parts to be practical, and it's being done.
In any case… I have "develop network of domain experts" in the back of my head as a wise thing to do.