On forums I find a lot of people asking about the interface used for the CCIE R&S Lab exam. Around 6 months ago, Cisco released a video with a tour of the interface, the narrator is not the most exciting in the land but you get the general idea and feel of the lab:
CCIE R&S v4.0 Lab Exam Demo
"This demo will familiarize candidates with the online interface that has replaced paper exams, which presents the virtual topology, test questions, documentation and tools. Strongly recommended for all candidates"