We have mentioned about the feature set on the first page. Here is a recap :

Spacing of PCIe slots is important if you wish to insert huge 3 slot cards. In this example, it is able to fit in 2 large card together with  a 8x running audio or Raid card.

One of the things that I like about is the X-Socket.  You can now save some money, reusing your older LGA 1366 socket heatsink on the new board. The bundles comes with a plate that you can mount at the back of the motherboard, allowing you to re-use your existing heatsinks. This concept is similar to what ASRock has for many years, allowing reusing of older heatsink but theirs is with 2 set of mounting holes on the board for clip on heatsinks.