I'm always amused when I see people, mostly web professionals, bitch about CraigsList.
The VC and bizdev types hate CL because "CL is just leaving money on the table. They need to understand how to make a profit."
Webdevs hate them because CL doesn't adopt whatever new design trend comes along, therefore CL "doesn't get UX", or webdevs hate them because of situations like this, where some webdev can't build his business off of someone else's platform.
This, compadres, is why you don't take your business public. CL has a staff of less then 20 people, they make plenty of bank while at the same time staying true to their own ethos, whether you agree or not. And the consumers seem to be coming back over and over. And yes, I have heard many people say that this is because CL has been around so long, that they are the 500 lb Gorilla that will never be moved. Uhh, are we on the same Internet? Tell that to Yahoo, MySpace, etc etc.
Here's a Wired article from 2009 that covers the exact topic of CL and site scraping. Maybe PadMapper should have read it first.
A list is only as strong as its weakest link. -- Don Knuth