Who are the most significant moral philosophers of the 20th-century?

The passing of Professor Foot, and my (uncontroversial) description of her as one of the "towering figures" of post-WWII moral philosophy, led to some interesting correspondence with various readers about late great figures in moral philosophy from the preceding century.  So the only way to adjudicate such weighty matters, of course, is with a poll.  Have fun!  And note:  I've included only late greats, no living greats in the poll. 

UPDATE:  So with more than 500 votes cast since yesterday, here is the current top ten:

1. Bernard Williams  (Condorcet winner: wins contests with all other choices)

2. G.E. Moore  loses to Bernard Williams by 240–224

3. G.E.M. Anscombe  loses to Bernard Williams by 296–158, loses to G.E. Moore by 280–164

4. Philippa Foot  loses to Bernard Williams by 316–134, loses to G.E.M. Anscombe by 238–196

5. R.M. Hare  loses to Bernard Williams by 318–130, loses to Philippa Foot by 253–178

6. W.D. Ross  loses to Bernard Williams by 307–125, loses to R.M. Hare by 204–193

7. John Dewey  loses to Bernard Williams by 340–88, loses to W.D. Ross by 223–152

8. Richard B. Brandt  loses to Bernard Williams by 351–39, loses to John Dewey by 192–126

9. Charles L. Stevenson  loses to Bernard Williams by 367–43, loses to Richard B. Brandt by 150–143

10. H.A. Prichard  loses to Bernard Williams by 359–41, loses to Charles L. Stevenson by 160–140

I'll open comments for discussion of the results either later this week or next week.