I submitted my thesis a little while back now, and having recovered sufficiently, I thought it would be good to expand on a couple ideas that came out of it. This type of addendum seems almost necessary given the fluidity of the field, where I've always had the impression that written contributions tend to go out of date almost instantaneously; looking at the findings in my report, I hope this proves to be the case with my own work.
Right now, the conversation in libraries is all about digitisation and not about born-digital. The problem here is that users of research libraries tend to value original material above digital, and inevitably come to digital resources with certain prejudices against such collections - once those prejudices hit the wall of poor functionality and, even, poor resource description, the impact these collections will achieve is going to be low. So taking on digitisation as a way to help meet institutional targets like basic access and preservation around your original material isn't going to engage users with digital collections.
Users seem to get more interested in digital collections when they're not derivative of original holdings, but rather treated by the library as collections in their own right. What that means is seeing digitised collections as born-digital. It makes sense on several levels: first, in many respects, the technical challenges of asset management are shared by both collections as they undergo their digital curatorial lifecycle; second, and probably more important, is that born-digital demands functionality.
The latter point is more subtle, because it's all in the mind, but if you digitise an old book and look to create an offering that allows you to turn the pages (just like a real book!) and throw in full text search, you're missing out. If you take those digitised images and metadata, and treat them as a born-digital resource, you're opening yourself up to some more interesting possibilities that your users might be interested in - the functionality that is unique to digital collections and gives them their own value that can potentially be above and beyond that of the original material.
Users think about stuff like reproducibility, sharing, collaboration, mashability, and they're expecting it more and more as they're conditioned by other online content out there. They're also idealistic: they talk about things like democratisation of knowledge and digital literacy, which often get lost as you battle through a multi-million image digitisation project. The current mass digitisation model may be tolerated by your established user research group, but it's difficult to see how it could ever impact on, say, the upcoming generation of potential researchers and interested public right now.
So on the one hand, born-digital is the admittedly tough challenge of grabbing our current cultural output and preserving it for future generations, which is a conversation that has really yet to get off the ground in most libraries; on the other, it's simply an approach to digital collections that sees them as unique resources in their own right could do something completely new and different for libraries who really want to engage users with digital collections.