Keep in mind that there are like 40,000 people there, so while obviously no number of assaults is acceptable, it's not like it's suddenly a hugely dangerous place on average. Stay with friends when moving through less-public areas, or ask for a guy (like me, if I'm at all available) to walk with you if you need to, and it should be fine. And, like akiko says, hopefully they'll implement more visible security next year in reaction to the problems this year. DragonCon is lots of fun! Hopefully there'll be less assholes around next year too - I hear LSU fans are known to be problematic.