Answer to my question, via support staff at wordpress:
--- On Wed, 1/20/10, Sheri - WordPress.com <firstname.lastname@example.org> wrote:
From: Sheri - WordPress.com <email@example.com>
Subject: [WordPress #444767]: Writing & Editing - WPToGo (Android Phone) and XML Activation
Date: Wednesday, January 20, 2010, 2:14 AM
> I recently got an Android-OS smartphone and it was reccommended that I
> use WPToGo application to update my wordpress.com blog on my phone.
> The app requires me to enable XML-RPC, however I am unable to locate
> that feature in my administrative settings on my blog.
> Is there a place to activate XML? Or is that an option only available
> to those self-hosting, or using wordpress.org?
> I will contact the creator of the app if it appears that is the
> problem, however, for now i simply can't figure out how to activate
> XML, and the forums don't appear to have any information on it at this
XML-RPC is automatically enabled for WordPress.com blogs. The URL is http://kellybwell.wordpress.com/xmlrpc.php if you need it.
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