Sorted by number of votes, then alphabetically:
Python - 14
Ruby - 7
C# - 6
C++ - 5
Haskell - 5
Java - 5
PHP - 5
C - 3
Scheme - 3
ActionScript - 2
Common Lisp - 2
JavaScript - 2
Perl - 2
ABAP - 1
Assembly - 1
BlitzMax - 1
CL (OS/400) - 1
F# - 1
Go - 1
Groovy - 1
Io - 1
Korn shell - 1
Logo - 1
Oberon - 1
Objective C - 1
Self - 1
Smalltalk - 1
Tcl - 1
Alphabetical Order ABAP - 1
ActionScript - 2
Assembly - 1
BlitzMax - 1
C - 3
C# - 6
C++ - 5
CL (OS/400) - 1
Common Lisp - 2
F# - 1
Go - 1
Groovy - 1
Haskell - 5
Io - 1
Java - 5
JavaScript - 2
Korn shell - 1
Logo - 1
Oberon - 1
Objective C - 1
Perl - 2
PHP - 5
Python - 14
Ruby - 7
Scheme - 3
Self - 1
Smalltalk - 1
Tcl - 1
All the rest of the languages received 0 votes.Also mentioned below were Arc, Clojure, Morpho, and O'Caml, though it wasn't clear whether they were mentioned for the sake of completeness or because they were someone's favorite language. So I'm not listing them as receiving any votes.
I think I got all the major ones, though. If you have a favorite not on the list, just add it below here, and I'll put in the next favorite language survey. I'll also put in in the result summary.
Edit: actually, maybe not.. I see I missed O'Caml. I would have also have liked to have included Arc. There have got to be some Arc fans on HN.
Personally, I would like to know what everyone's one favorite language is. But if you select more than one, I don't see it as a big deal. That information would also be valuable.