What I'm writing here is because I agree with what James Tauber is writing:
Sites that aggregate just need to provide a mechanism where users can point to their data hosted somewhere else rather than have to re-enter their data in multiple aggregators. Aggregators then keep customers based on the value of their aggregation, not the lock-in of being the hosts of people's valuable data. People who want hosting for their pictures, blogs, etc can use hosting services to do it. But their choice of hosting service should not impact their participating in aggregation and the social aspects of micro-content that follow.
There's the issue of making money off of internet applications. Take for instance Amazon, they're allowing you to download a lot of their information on books (and more). I shop a lot with them as they've gotten a lot of things right. Ordering is easy, you can combine shipments to save some money, etc. But, a lot of their use comes from the user-provided reviews of the books. That, combined with their customer data, gives them an edge over other online bookstores. But they hoard that information that, basically, we gave to them. Amazon is a prime example of how to hoard information in a friendly way.
I agree with James that "social" information like this, contributed by individuals, should be freely placeable everywhere. You could host it yourself, you could put in on somebody else's server (paying money?), etc. And irregardless of this "hosting" choice, aggregators should be able to access your information. For instance, bookreviews. You make a bookreview and many online bookstores could use your review to help their customers. Instead of submitting your "social" information to one aggregator (amazon) and not being able to touch it anymore (apart from copy-pasting your text).
Now to the construction industry. They way I think about it now, I want this sort of generic, social information freely available too. (Free not really in the monetary sense, though that is part of it, but more as in "free to move around, free to (re-)use").
An example? In eConstruct we initially designed our "catalogue server" so that it didn't matter whether you hosted your own catalogue server or whether you used some more centralised service that did this for you. "Higher level" catalogue servers could aggregate multiple "lower level" catalogues or catalogue servers, to provide a single entry point for catalogue queries. Handy. This would enable individual bigger companies to aggregate their preferred suppliers in one company-internal catalogue server, so that it would be easy to order from those preferred suppliers. Probably including a pre-calculated lower price because of the higher volumes. Or aggregators could provide an additional service by doing some quality filtering on the catalogues they aggregate, filtering out the bad apples.
That was 2000 till early 2002. The idea is still valid. The wish to have good content available in a computer-readable format is still valid. But, stuff like this should not be used to create the same old information-hoarding entities that just use a fancier way to transport their propietary information. That won't help the construction industry along. Interoperability is what we need. Shareable data. My dissertation will probably include a term like "shareable specification data" or something like that.
My name is Reinout van Rees and I work a lot with Python (programming language) and Django (website framework). I live in The Netherlands and I'm happily married to Annie van Rees-Kooiman.
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