Check out the top 40 <a href="http://www.magazine.org/editorial/14408.cfm">magazine covers</a> of the last 40 years. The problem is that there is a stark difference between design and semantic "best", with (unfortunately) too much weight placed on semantic. My re-ranking would be:
<ol>
<li>People Mar 4, 1974 (Mia Farrow)
<li>Blue Oct 1997 (Diving guy)
<li>National Geographic Jun 1985 (Female Kurd in red)
<li>Interview Dec 1972 (Christmas dual-spread)
<li>Playboy Oct 1971 (Black bunny)
<li>National Lampoon Jan 1973 (Shoot the dog)
<li>Economist Sep 10, 1994 (Camels got hump!)
<li>Harper's Bazaar Apr 1965 (Pink Polka-head)
</ol>