Dragon*Con fans come out in great numbers, and in great costumes. As a multi-cultural event you could expect to see multiple genre's of costumes; sci-fi, comics, horror, fantasy, literature, music, but you may not expect to see wo much effort, or lack of costume ;-)
KP tours the six hotel convention for some of the more interesting costumed fans to show off the range of what you may see if, and when you attend. Plan on attending Dragon*Con next year September 2-5, 2011.