Selecting an <option> in a list box no longer focuses the list box, but clicking the scroll well or tabbing to it does focus it. http://trac.webkit.org/projects/webkit/changeset/18338 seems to be the cause.
*** Bug 12008 has been marked as a duplicate of this bug. ***
From bug 12008 comment 3 - This issue is covered in <rdar://problem/4901834>
Committed revision 18989.