Selling on Cragslist is definitely more hazardous then buying. If you are selling there is a danger of your property being taken from you during the presentation (or bodily harm to you) even if the meeting is in a public place, as the lady in the above story.
If you are the buyer then the danger is bad or counterfeit merchandise, which you protect against by bring a loupe, small scale, and magnet. One might argue that "Hey, they can rob you of your money if you are the buyer". Yes, that's true but the "bad guys" generally don't have property or cash to bring to a meeting (or won't), so it is easier for them to play the buyer.
Monkeyman's suggestion to buyers about bigger deals is good advise - first meet to just see an example of what the seller has, and then complete the transaction at the bank. This also puts your sellers at ease when you suggest a "first meeting". So, determining the size of the deal before the meeting (e-mail or phone) is important for buyers.
The Danester.