Originally there were going to be Express Card graphics cards but it was found the heat and power required wouldn't work. Heat is the main problm. Can't keep it cool. The upgraded Nvidia graphics cards are Mini PCIe, but they are made to each laptop and are not interchangeable. It has to come from the laptop maker and be mad for your model laptop. The PC makers don't sell them that way but you might get a "replacement part" or very slim chance of an Ebay broken laptop of the exact same model. Even then I don't know if it will work in a laptop that caame with Intel graphics instead of Mini-PCIe graphics. Normally it only works going from say a 128 MB card to a 256 MB card.
The intel 965 is better than the older Intel laptop graphics. The Intel graphics card uses a lot less battery in a laptop than an upgraded separate card.
The best use for the Express Card slot I've found is very fast data transfer for an external eSATA drive. It's much faster than USB2. Get an Express Card to dual eSATA card or even a single eSATA and an external eSATA drive.
I think this is for Intel 950 laptops which are one version older than Intel 965 and the upgraded video cards now use a different sort of slot, so it may not apply at all and they explain why it may not work at all even with the proper slot and card.