Not everything being a resource, for one, and not everything being naturally represented in a URI. It's possible to encode just about any information in a URI,

Not everything being a resource, for one, and not everything being naturally represented in a URI. It's possible to encode just about any information in a URI, it doesn't mean it isn't a kludge and a force-fit. Take a very, very simple (and common) use case: https://maps.google.com/maps?q=Newark+International+Airport,+Brewster+Road,+Newark,+NJ&hl=en&sll=40.697488,-73.979681&sspn=0.940177,1.685028&oq=newark+li&hq=Newark+International+Airport,+Brewster+Road,+Newark,+NJ&t=m&z=14 https://maps.google.com/maps?q=Newark+International+Airport,... Holy God would you look at that URL. It doesn't refer to a resource. In fact it refers to application state. This is a gross abuse of the whole concept of a URL, but the folks at Google aren't idiots - they know this. But the fact of the matter is that Google Maps is not document-based, and people have legitimate need to transport application state, independent of the semantics of the information they're looking for. Even something as simple as showing my friend the same map I'm looking at so we can talk about it requires bending the role of URIs wildly out of shape. Even better example: https://maps.google.com/maps?q=restaurants+around+Times+Square,+Broadway,+New+York,+NY&hl=en&sll=40.691572,-74.10347&sspn=0.235066,0.421257&oq=restaurants+around+times+square&hq=restaurants&hnear=Broadway,+New+York&t=m&z=16 https://maps.google.com/maps?q=restaurants+around+Times+Squa... One can argue that the previous link was clearly a reference to the airport, and there can be a URI for it (which wouldn't transport application state, substantially hobbling its use, but whatever). This link refers to "restaurants around Times Square", which isn't a logical entity, and whose relevance to the end user depends entirely on the application state being transported (e.g., zoom level, center point, filtered results, etc). Every time these insane-o URLs get brought up the URI-acolytes seem to end up suggesting that maybe we shouldn't have rich, interactive maps or such things, that we should force software into roles that play nicely with the document-centric, URI-friendly schemes. I for one believe that software serves users first, and methods to locate and specify information needs to adopt its users needs, not the other way around.