Update: December 8th, 2014
The API now supports write actions as of v2.2. See more in the related blog post:
What’s new in this release?
- Creating questions and answers
- Editing, Deleting, and Flagging
- Improved OAuth UI on mobile devices
- …and lots more
To answer your first question, the API does not currently support writing actions.
However, the API roadmap indicates that these features are currently being developed. I've quoted and summarized the relevant excerpts below:
For version 2.0, the biggest new feature will be user authentication. Currently leaning towards OAuth2.0, although this is subject to change. As a consequence, access to some private information (inbox notices, some voting records, maybe contact information, etc.) and privilege restricted information (deleted posts, flags, and so on) will be possible.
With any luck, we'll be working on this version sometime this calendar year. Given the scale of the planned changes, [SE expects] it to take a full 2 months to get it into a beta-able state.
Version 3.0 will be all about write access. Frankly, write access is incredibly dangerous, and quite complicated, so it really needs a whole release just to itself.
[SE has to keep good quality and not break any existing apps with these changes.]
[SE has to also work on API support various display extensions, like MathJAX.]
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