Okay, I'm not sure I see exactly why it would be better to post from googledocs to your blog (especially, if you use blogger and are already logged in via your google login), but here goes:
did you know that you can publish directly to a blog via google docs? http://googledocs.blogspot.com/2008/07/live-blogging-with-docs.html
One caveat, though: scheduling/future posts do not seem to work via this method. Even if you edit the date in blogger, it doesn't force it to future post.