My intention with this poll was to be kinda vague, so that people would respond about what they like the best instead of thinking of one particular instance of usage. Usage could be where ever you need to manually name something: CSS classes and ID's, programming function names, file names, usernames and passwords, basically anywhere you can't use, but benefit from simulating, spaces.
Turns out the vagueness was problematic. For example, you might love hyphens (I do), but you can't use hyphens when naming PHP functions. The poll results would have probably been more useful if it was limited one one particular language. Ah well. Inherent flaw aside, camelCase took the win at 45%, and hypens edged out underscores for 2nd place, 28% and 27% respectively.
New poll in a few days.