Generation 2 is has been out for the past year or so. It allows you to manually switch between the integrated graphics and discrete GPU without having to reboot. This takes on the order of 10 seconds to close down any blocking applications and then switch over. There is no reboot. The Asus UL80Vt is an example of a laptop that allows this. For the record, I have an Asus UL80Vt on order.

Generation 3 allows the switch between the integrated graphics and discrete GPU to happen seamlessly. This is obviously better than the Gen 2 product. No manual switching is needed. No closing down blocking applications. No 10 second delay. There is no screen flicker or screen blanking. The delay has been reduced to 200 milliseconds, which for all intents is what we call instant. However, the Gen 2 hardware has an 11% advantage in battery life over the Gen 3 hardware in real world usage.

Will I cancel my Asus UL80Vt order? No.

Why not? First, it takes time to get anything ordered through our Purchasing Department. Once the process is going, it is better to let it run its course. Second, the Gen 3 hardware is not available for order, yet. Theoretically it is available today, but I just checked Newegg, and it is not there. Third, I am likely to use the discrete GPU all the time when plugged it, and the switch over to the integrated graphics when I am not plugged in.

In short, Gen 3 is better, and I would love it have it on my laptop.