Cardhub.com, a gift card buy/sell/trading site, has launched a new social network-linked gift card exchange to allow people to buy, sell, or trade gift cards without the overhead involved in using a service.  Why is this better than Craigslist?  The idea is that with access to the other persons social network profile (aka Facebook), people can feel more comfortable doing business with them, versus some random person they might meet on Craigslist.