Craigslist really is a roll the dice, i've sold computers cars etc on there and you really have to be careful. I guess you have to be attuned to how the person is acting about the trade. I personally would never sell bitcoin on craigslist
I think selling bitcoin on craigslist would be a great way to get more people to use and adopt bitcoin.
What I would be afraid of is selling large amounts (like thousands of dollars worth) as there would be a greater incentive for the buyer to try to rob me.