I've now been at ISWC05, ESWC06, ISWC06 and ESWC07, and I fancy I can detect some change of tone over that period. The first one seemed to have a lot of folk talking about interesting logics they've thought up, and how to express rules, and how to implement triple stores, in soporific detail; the later ones are a lot less defensive about the whole SW notion, and more concerned with Web-2.0ish issues of how you make realistially usable (as opposed to merely non-theoretical) applications, what performance issues there are, and how do you actually get all these triples.
There was a certain amount of workshop- and beer-based conversation about just how the SW is different from Web-2.0: there wasn't a clear one-line conclusion, but I have the vague feeling that the cheerful-cowboy Web-2.0 approach is running our of steam a bit, as folk confront the limitations of what you can actually do with the APIs that this or that service makes available, just as the SW approach is gaining confidence, and pulling/pooling information in much more sophisticated ways.
Perhaps I've just got better at giving the funky-logic talks a bodyswerve, but I think this represents a change in the community, from a CS-heavy to a developer-led one, which now has the leisure to be interested in practicalities.
