I agree, to some extent, that a standalone ebook -- i.e. something that's not only supposed to be self-contained, but is technically constrained to do so -- is probably a dead-end, or at least better suited to the printed format. But that doesn't necessarily mean all content should be unbounded, or that people will want a platform that lets them hop around to different texts. I would argue that bounded content is not only desired by more people than you'd think, but it's likely necessary in some situations (or for some people) to comprehend some texts. So, while I think Logos (and services like it) are interesting and will probably enjoy a healthy uptake, I don't think they're going to 'end the ebook' as such.