The new Vaio does not comes with a discrete GPU. Sony explains its absence by saying that there is no need of a discrete GPU as it may result in poorer runtimes. Also, a common man on the road may not be doing gaming on the road and that is why they are offering Power Media Dock that adds a very powerful GPU and some other things like ATi Radeon HD 6650M.
This GPU, as we mentioned in the Sony Vaio Z 2011 review, allows you to run up to four displays at the same time. It also adds blu-ray optical drive and myriad ports including 2x USB 2.0, 1x USB 3.0, LAN cable and HDMI port.
Is it worth it? i guess the benchmark graph given below explains everything
There is no battery inside the power media dock and thus you need to ensure that it is always connected to the AC adapter in order to function.