Correct, not carpet. It is ArmorThane which is similar to Rhino liner or Line-X: http://www.armorthane.com/armorthane.cfm
It was professionally sprayed on by an ArmorThane dealer. Its sprayed directly on the MDF, I only prepped the MDF with 220 grit prior to spraying.
I originally wanted Line-X, but the local Line-X dealer wanted $350 to spray the two boxes, needless to say, I obviously didn't go that route. I found a local ArmorThane franchisee that had recently started his business, he sprayed the two boxes and tray for $70, only asking to spread the word for future business.

Here are closer pics