Uh, no it doesn't. I never got a single spam, and I've sold about 10 things (mostly electronic) over the last year. Not one of hte people flaked on me or tried to haggle once I met them. Yeah, they haggled before (on the phone or via email), but once I met them, everyone was nice and kept to the agreed upon price.
1 - I refuse to hold anything (first person to show up with cash takes it)
2 - no haggling on the spot; I'll turn you down on principle
It's a fucking hassle. I buy a new macbook every 12-18 months and craigslist the old one (and the same with phones). I take good care of my hardware and carefully point out any scratches or nicks in the craigslist listing. People still try to knock you down 10% or 20% when they come.
Problem with this app is there is a limited amount of users while cl has 90% of the market. So you will probably still get a better deal on cl.