I've had a lot of heated debates over this last 18 months regarding the DDA and what it means to developers. Effectively, it cripples us (no pun intended) if we actually adhere to it in full.
I came to the reluctant conclusion that all we can do is try as hard as we can to produce accessible output, but if any degree of creativity is to be maintained, something has to give. There is a lot you can do with plain vanilla code and CSS, but there's a whole world of possibilities to web design and forcing all business sites to adhere to a standard that lobotomises really creative content to a large extent is causing more than its share of problems.
There's a cost hit too. Many of my clients are becoming nervous about the DDA and are testing again and again to ensure compliance. Others seem less bothered, but the DDA has certainly opened several very large cans of worms.
If anyone knows how to include all the nice bells and whistles we have been able to play with in the past and not offend someone, somewhere, please get in touch.
My own solution in the long term may even regress to a dual site approach - one for visual browsers and one for text/screen readers and similar. Go figure.