Accessible data table

Hi all -

I'd like an opinion on the accessibility of our data tables. I think I've 
covered everything including:

1. Table caption elements.
2. Proper table structure including th, thead and tbody elements.
3. identifying relationships between columns and cells using scope, id and 
headers attributes
4. A meaningful table summary attribute.

Is there anything I'm missing?

http://mit.edu/ocwhq/author/cmstable/100/6columns.html

Thanks in advance.

--
B.K. DeLong
Web Production Specialist

MIT OpenCourseWare (OCW)
Massachusetts Institute of Technology
Building 9, Room 215
105 Massachusetts Ave.
Cambridge, MA 02139-4307

email: bkdelong@mit.edu
http://bkdelong.mit.edu