This issue is discussing an aspect of the new Use Cases and Requirements for Web Mapping (which is a great initiative and hopefully something that can be collaboratively developed by the Web standards and Web mapping standards communities. Those who show up write the standards!).

I have been thinking about whether having a default map provider should be part of the use cases / requirements. Video is a pretty close analogy to maps in many ways. I'm concerned that it will end up being a bit like having a browser-default video provider: not something that most users would want, but certainly something a browser vendor with a video service would like to have. This was also a question at TPAC last year.

Default map provider is something which certain web components already do (as noted), and that is a standard at a level that I don't believe is where maps should be standardized i.e they bury / don't provide the URL. I think having maps which support URLs for content retrieval goes a long way to obviating the need for having a default map provider (see Manual and/or Automated Map Creation and Layers - Add Using Standard URLs slightly below that).

It's incumbent on us (the mapping / map provider community) to make it easy to find target(s) for those URLs, which we're currently trying to do by getting support for MapML built into as many existing map servers as possible. If OpenStreetMap (say, to pick a non-commercial example, but not wanting to limit examples to non-commercial services, could also be open data/government providers) was to support MapML instead of iframe embeds, then they could provide valid MapML document so their maps would be available for embedding at a source URL.

In sum, I believe that instead of requiring (or even allowing!) default map provider, we should require URLs for maps / map content. Thanks for sharing your thoughts!