so caveats.
1. it's one of the many displays being seen by parts suppliers in china. It's possible it's not for the actual iPad 3. It's what is claimed to be an iPad 3 screen that has been floating around the net.
2. Parts frequently start churning out, as products go into production. iPhone 4S parts ramped up prior to it's release. Note, iPhone 5 parts did not ramp up and was a clear sign it wasn't heading into production. I don't know the exact process by which this happens, but it happens.
3. "Confirmed" that the iPad 3 display parts that we have been seeing are Retina.
arn