A modern video card uses lots of power and needs lots of cooling so I am not really impressed with mobile video chips.
Thunderbolt is more exciting. It's PCIE over a cable. So you can have an external graphics card and enclosure. Plug power cable into wall. Plug thunderbolt cable from video card into notebook and voila.... top end graphics power. With some variations the thunderbolt tech the cable could carry enough power to power the laptop over the thunderbolt cable.
The great thing is you still have a great portable laptop that can focus on saving power and having a great battery life but can be upgraded on the spot to a powerful gaming computer when you really need performance. The same setup can also upgrade a desktop computer in the same way so you can have a couple desktop computers and multiple notebooks and only need to buy one high end graphics card which can be quite an investment.
This tech is so revolutionary it will lead to a new desktop form factor without slots on the motherboard. You'll have a small CPU box with a closed loop liquid cooler. It might even be completely powered by a thunderbolt cable. You will then have a bus/hub box that will be similar in many way to a classic desktop in size. The difference here is that it can be large or small. It can have many slots or just one. It can be have many type of form factors.