I'm using an older version of WordPress (2.9.2) provided by my web hosting company. But I decided to try the version available at WordPress.com; I'm unsure whether it it based upon the latest version available at WordPress.org (3.0.1).
My clients that use JAWS typically use Internet Explorer because it has tended to work better with JAWS (though Mozilla Firefox has come a long way). So I've been trying to use JAWS 11 with IE 8 to post blog entries on my WordPress.com account.
The major difficulty I'm having is that JAWS doesn't think the site is composed of web pages. This severely limits how JAWS can interact with the site. JAWS contains lots of keystrokes to make web page navigation simpler. Navigation quick keys are a letter that move from element to element e.g. H for Heading, E for Edit box, B for Button. Lists of form elements in a dialog box exist for links, headings, all form controls, specific form controls. None of these navigation techniques work for me because JAWS doesn't think it's on a web page. I get a "This feature is only available from within a virtual document such as a page on the Internet" message when attempting any of these commands.
To interact with forms, JAWS does require forms mode to be active. This often happens automatically with the latest version of JAWS though sometimes (and for older versions) pressing Enter when on the form control is required. Once JAWS is in forms mode, tabbing moves the PC cursor between tab-able elements such as form controls or links. The behaviour that I'm experiencing on my WordPress.com blog is similar to having the PC cursor enabled i.e. I can only tab between these tab-able elements. This means that I'm unable to read static text. Tabbing is also a very inefficient method for navigating a web page especially when it contains a lot of form elements and links.
There are many ways to exit forms mode e.g. pressing the ESC key, NUM PAD Plus, refreshing the page (see Using Forms with JAWS and MAGic). But none of these work.
I have had better luck when using Mozilla Firefox 3.6.8. I do use both browsers but my visually impaired clients tend to use Internet Explorer. It's much more challenging for the typical JAWS user to learn a new software application as compared to the typical sighted person. WordPress.com needs to be accessible with this widely used screen reader and web browser. Most discussion surrounding WordPress accessibility has been for screen reader users as consumers of blogs; we also need to support them as creators of content.