Maybe it's just me, and it's probably wrong, but more than once I pre-processed XML data by replacing all the "namespace:tag" by "namespace-tag" so that I can easily parse the XML without having to care about namespaces. I've never been convinced that this feature has much use anyway.
You never understood what they were actually for, then. The namespace will have a schema, and the schema can be used to validate the elements of that namespace. Not used in a "just import the data!" scenario, sure, but a lot of people who use XML do care about that kind of validation.
> The namespace will have a schema, and the schema can be used to validate the elements of that namespace.
That's one option. But a Schema (or DTD) is not mandatory, and not all schemas can easily be linked (few tools handle relaxng or schematron for namespace spec).
The core purpose of XML namespaces, and that of any namespace really, is better modularity and compositionability by preventing name collisions. This is useful when manipulating XML via XML (e.g. XSL, Genshi, ...) or when using multiple XML dialects in the same file (either because they're orthogonal or because they complement one another) for instance. You could do it by explicit prefixing à la C or Objective-C, but it tends to get dreary, requires everybody's cooperation and generally looks bad (not that xml namespaces look overly sexy).
