What is a core service?

Bob Schrier of AutoGraphics writes about digitisation and posits that it should be perceived as a core service of libraries. I do agree with the him in that digitisation is indeed something libraries could (and perhaps should, with an emphasis) consider as an offering that both makes sense considering the mission of (public) libraries, community needs and the existing and conceivable competences and capabilities of libraries. At the same time, however, I am not entirely convinced that it would be a good idea to dub digitisation as a core service at least in the long run. At the moment digitisation could undoubtedly be a significant offering and a feasible service but it remains to be seen how long time this state of affairs should and would remain. I am not saying a definite no to Schrier's proposal but in order to avoid establishing unnecessary and potentially harmful orthodoxies I would probably define the core service  in terms of helping library users to access and maintaining access to both their personal and publically available information and knowledge. In this respect digitisation is at the moment a potentially powerful instrument for delivering that service but widens the understanding of the principal problem, that of the availability and accessibility of information in the widest possible meaning (comprising entertainment, bildung, learning, professional needs, social, cultural, heritage-related and emotional aspects).