The Z68 chipset allows the use of the CPUs onboard gpu core just like a H67 board, they have various display connectors on the back.
They also have SSD caching, Lucid Virtu and Quicksync.
SSD caching,
This allows you to use a small (20GB'ish) SSD along side a HDD with the OS/programs already installed, this means its speeds up acess times as it "caches" the most common data.
Lucid+Quicksync,
Quicksync allows some programs to use the onboard gpu core to speed up video encoding times etc, Lucid switches off (in to idle) a discrete graphics card and uses the onboard gpu core for simple tasks. saving power.