The docstrings of display-time-world-list say "Alist" whereas if I'm not
mistaken the entries are lists, not pairs.  Perhaps the docstrings could
say just "list" so nobody tries to add to them as an alist.  (Doing so
causes an error from M-x display-time-world.)

2010-07-16  Kevin Ryde  <user42@zip.com.au>

	* time.el (zoneinfo-style-world-list, legacy-style-world-list,
	display-time-world-list): In the docstrings say plain "list" not
	alist, as the list elements are not pairs (but lists).
	(display-time-world-display): Rename parameter from `alist' to
	`world-list' as it's not an alist as such.