Yes. It is in the interests of Apple, Google and other smartphone makers to provide APIs to their device drivers so that others can write apps, however, I don't think that such features will be specifically incorporated into the HTML5 specs.
Let me rephrase and narrow your question with an example:
I don't know the answer to this question. I've not had a chance yet to explore writing smartphone apps in HTML and JS so I don't know the details of how Google Goggles, for example, controls the camera. Does anyone know what Goggles is written in?
This does bring up the distinctions between web pages and apps. An app uses all the technologies of a web site but packages it to run independently (no browser required) on a target device. Also, an app asks for permission to connect to your device's camera when you install it. Do we really want a web page to be able to snap a photo without first asking permission? Suppose that the camera is accessed not by code under the control of the site's webmaster but from code embedded in a ad served up by a third party service?
Smile and say "Cheese".
Author: HTML Manual of Style