Why aren't any POST methods available?
Being able to post new questions and answers would be very interesting.
They have been very clear that version 1 of the API will be read only and they will be revisiting the POST type features (like adding new questions and answers) for the next version of the API. You can post and vote for the features you would like to see in the next version here. You can also view any feature requests which have been deferred to some future version wit the status-deferred tag.
Read the blog entry about it