People who use the WordPress web interface on a Mac may notice that the size of the text in the editing boxes is too small to read comfortably. This is particularly so in Cocoa-based browsers including Safari and Camino. It's not a problem in Firefox and Mozilla, both of which use Carbon.
The solution is to set the text size in admin.css, which you can find in the CSS section for "textarea, input, select". I set it to "font-size: 11pt;", although the choice is up to the user. Can I suggest that something like this be included as standard in WordPress?