Semantics schemantics. You can't possibly expect a device to competently translate your design into a layout that makes sense for both the content and the screen size.
@quarterto, agreed you can't expect a device to completely decipher all forms of content but you can ask it to do much better. You also can't expect a developer to deliver for all form factors.
@rnassar, agreed on the alternative forms of consumption. We can probably move more of that into the devices natively.
My bad on the reply (or lack thereof). I agree to date responsive gives a generally better experience for most sites. I don't think however it's the best solution for mobile design.
It compromises usability through a changing of the interface, there is no reduced markup size and it's a very costly endeavour.
Should also consider completely alternative means to consume web information on mobile devices. Evernote and Instapaper are two tools that have completely changed how to actually read articles and content. While they don't let you browse sites in the same way, once you've come to the actual story or article you are looking to read, tools like this provide a great alternative over a mobile web browser. Offline reading, article saving and remembering where you left off are all possible with these tools, but not in a browser.
@yoshi Agreed, just looking at collective overhead to design across the prominent form factors now, I fear the day when we have 20 different forms that need attention.
And I think your suggestion could speed innovation as we evolve new form factors... rather than convincing the masses to build for your device, a manufacturer can work from existing conventions to adapt the content to their particular need.
I would argue that the beauty of web is experience and not semantics. Semantics are just a means to an end. Responsive design in its current form gives the designer/developer complete control over the experience. If you take that away, and allow the browser to define the experience than I think we are losing something important.