I'm working on improving the accessibility of an IT software vendor site that has many diagrams in images.
I've given a first shot at implementing accessible descriptions of these images with the longdesc attribute. I'm not sure if I'm really using it the right way. Take a look, there are two images on this page using it:
looks good to me. i would provide some mechanisms of getting to the longdesc for browsers which don't expose it directly to the user (heck, even in firefox, i had to right click the image properties, copy the description link, paste it in a new tab). i'm not saying that the dreaded [D] tag is the answer, but possibly something similar in a slicker way (e.g. a nicely worded link, rather than just [D], along the lines of "read a description of the above diagram" or something)