While the previous MDXs as well as the current RDX could NOTsupport a rear trunk mounted bike rack, the new 2014 MDX in fact CAN supportit.
This is a completive advantage as none of the Audi or BMWSUVs can support the trunk mounted bike racks (at least not according to Thuletesting), requiring expensive and in many cases not esthetically pleasingalternatives. The Infiniti JX35 can support it.
The best rack that I found and have been using is the Thule9003 Platform. Its extremely easy to setup, has built in locks for both therack as well as the bike. VERY secure on the car and doesnt damage the paint.And is MUCH gentler on the bikes as well as more secure and easier to set-upbikes on it.
I have a great picture of the rack on my MDX but the system is not allowing me to add pictures to posts yet. It's rock solid on the MDX. In fact its so securethat you can sway the car (while parked of course) by trying to move the rack,the rack itself didnt move even an inch.