So I haven't really thought about the detail of this.  It's more of a musing than an informed article.

I've been reading various news articles about the advancements in touch screen technology and how it will become ubiquitous over the next few years. Microsoft are researching the possibilities of having the main UI for Windows and even the possibility of combining touch and voice recognition in an attempt to do away with the keyboard and mouse altogether.

So is that an improvement in terms of accessibility ?  We already use voice recognition quite successfully to aid navigation and the technology is improving all the time, so that it is becoming a viable option for composing text content - though editing can be quite painful.

But if the design of the User Interface shifts to tough screens will this make life easier of more difficult ?  Will the navigation be easier ?  Think of what makes an iPod Touch or iPhone's interface so easy to use.  It's all about flicking a finger across the screen to scroll around, or moving your finger and thumb apart or together to expand of shrink an image.  How does this work for someone that can't currently control a mouse or keyboard ?  If designers aren't careful they could add a layer of complexity here that makes life even more difficult for disabled users to use their websites.  I haven't read through the WCAG 2.0 document yet (it's on the list now that it's in final stages of ratification) so I don't know what it has to say about this subject.

In terms of testing, we'll still be able to check the code that underlies the new interface so it doesn't make a great deal of difference to the bulk of our tests.  And if there are Accessibility guidelines that relate to the touch screen technology we'll review them and implement them if possible.