Trek #7 published a fan poll on various subjects including best episodes. It was reprinted in The Best of Trek in April 1978. The results were:
1. The City on the Edge of Forever
2. Amok Time
3. Journey to Babel
4. The Menagerie
5. The Trouble with Tribbles
6. Shore Leave
7. Balance of Terror
8. The Enemy Within
9. The Naked Time
10. Mirror, Mirror
Wow, you are the man. I really thought I wouldn't get any response!
That's a great list that would probably be similar to one in 2012!
Not one of them is bad by any stretch. My list wouldn't include Enemy Within or Trouble but still a very good list.
Shore leave in another 'fun' episode like Trouble and I prefer it, but probably not my top ten.
Thanks for finding that!