I've sold my iPhone 3 and original iPad via Craigslist and a meeting at Starbucks and had easy transactions. I'll sell iPad 2 this Saturday the same way.
Since I'm a petite girl, I've always brought along my husband just as a second person, and we all sit down at a table and the buyer gets to thoroughly inspect the original packaging and unit, and make sure it turns on, apps launch, etc.
I've heard Craigslist horror stories of people picking up the iPad and running out of the coffee shop, but so far I've met nice, normal people that wanted the transaction done as quickly as I did.