Hi Roger,
Thanks for your points. My responses below. Including a bit about GML that should really be in a different thread!
Yes. I also think the GML discussion must be moved somewhere. I actually did not want to discuss about GML but more about OGC standards in general. I know WFS is totally based on GML (for the moment) but the, maybe, most successful standard from OGC, WMS, does not have anything to do with GML.
So here my argument is that: by setting up a query level and installing a capable software on the providers directly we are improving these databases.
But surely these people can search their own database already. If you are providing a cheap and easy web interface for them then that is a tangible benefit but could equally be done centrally with a branding for the institution. It doesn't physically have to reside with them and be maintained by them - though that may be the best for many organisations.
Yes. I think most of the users will like to have the interface in their own servers, I don't think centralized solutions will, now, work. Actually other reasons to create this local interfaces is to let them see the data the way is going to be published on external sites. It would be great if the provider software could include a template fot his Querytool that will look exactly the way GBIF does. I remember to tried that but GBIF is not using XSLTs at the moment.
I have used this argument for a while already when convincing data providers: by joining GBIF they are not just only making their data available to the community but that they will also benefit of the tools that are appearing for them based on TDWG standards. I think it is a good deal, make your data available and we will help you to improve it with standard tools from the community for no cost.
This is just as available if the indexing is outsourced from the data owner I believe but is difficult to discuss abstractly here.
But remember that also some users will like to use this without having to share their data first.
Regarding the comments on GML app schemas, again, I did not want to start the discussion on this. I was more talking about WMS, WFS, Catalogue, WPS, etc. standards. They are not dealing with the semantic or modelling problems, they are dealing with the software interoperability problem. I think this is also part of TDWG bussiness.
I am not an expert on GML to answer some of your questions but we should maybe try to someone involved. I know GML is not restricted to geographic features and that there is some movement in the direction of GML profiling. But again this fits very well in another post.
Javier.