I have been using Craigslist for advertising rentals since 2008. It is still a valid lead producing source. I am in the Charlotte, NC market. Even with hundreds of ads posted and re-posted throughout the day, it is still worth the few minutes a day to post there.
Craigslist has improved their site enough where I haven't been "ghosted" for a long time. The search function for prospects is more user friendly. With the absorption of Postlets by Zillow, it will be even more important for me to use it.