Publishers don't just publish, so even if the world comes up with some way to get words directly from the writer's nib into some perfectly-paper-like electrophoretic e-book reader, the role of the publisher won't have gone away. But if the world also comes up with a way to figure out which raw manuscripts are wheat and which are chaff - and it bypasses the current quality filters of the agent -> publisher -> retailer supply chain - then the world might be on to something.

If they don't need us to recommend what to read and they don't need us to convey their chosen author's words to them, we will need to think of something else to do with our days. I tend to watch* the music industry for ideas and then think about whether they might manage to jump the gap into book-world. This 'music discovery' site (link to summary. click banner to go direct.) is interesting. Explore, rate what you find, and shape the collective verdict. Of course, 'experimenting' by listening to a new tune might take 2m40s whereas reading a novel on spec might take all day. But that's why now is a good time to think about the future, not when the kinks have been worked out and it's already happened.

* 'watch' is too active a verb. 'take note when I stumble upon facts about' might be better - what Eddie Izzard calls 'passive research'.