OK, with the template upgrades we just put in, this COULD be an old template laying around that is preventing the new code from showing you the most recent sizes of text areas.
Reason I believe that: Old text areas were too small. New ones are not.
If you had template override files in your theme, do this: temporarily REMOVE them (download to your local machine and delete them from the server). Then try it again. I found this clears up most formatting issues because the old templates didn't format things quite right (which is why we revamped things).
Try that out--if it doesn't work, give me a link to the page and let me have a look.