I did a composite ranking of revenues and attendance (averaged over the past 4 years) - I think this is a pretty good proxy for the top hockey towns:
1. Toronto
1. Philadelphia
3. Detroit
3. NY Rangers
5. Montreal
6. Dallas
7. Colorado
8. Minnesota
9. Vancouver
10. St. Louis
11. Los Angeles
11. San Jose
13. Tampa Bay
13. Ottawa
15. Columbus
16. Boston
17. Calgary
18. Chicago
19. Edmonton
19. New Jersey
---------------------- Above is what a 20-team league might look like
21. Washington
22. Florida
23. Buffalo
24. Atlanta
---------------------- Above is what a 24-team league might look like
24. NY Islanders
26. Pittsburgh
26. Nashville
28. Phoenix
29. Carolina
30. Anaheim
1. Toronto
1. Philadelphia
3. Detroit
3. NY Rangers
5. Montreal
6. Dallas
7. Colorado
8. Minnesota
9. Vancouver
10. St. Louis
11. Los Angeles
11. San Jose
13. Tampa Bay
13. Ottawa
15. Columbus
16. Boston
17. Calgary
18. Chicago
19. Edmonton
19. New Jersey
---------------------- Above is what a 20-team league might look like
21. Washington
22. Florida
23. Buffalo
24. Atlanta
---------------------- Above is what a 24-team league might look like
24. NY Islanders
26. Pittsburgh
26. Nashville
28. Phoenix
29. Carolina
30. Anaheim