I have not seen this video on YouTube but I found a write-up in a french technical magazine addressing this issue.
The magazine (MacGeneration) writes that Apple now offers a new system in their new MacBooks which allow the machines to choose which graphic card it uses depending on the program you are running on the machine. They claim however that this automatic change between the two build in graphic chips does not function as properly as it should.
They say that it is possible to see in the system preferences which chip is currently doing the work, and when they tested this they were amazed at the results.
They further claim that the Nivida GeForce 330M starts its work as soon as the programs iMovie, iPhoto, and Pixelmator start up which is to be expected as these programs can use the extra horsepower, however the 330M also starts up when you run the programs Twitter client Tweety and Nambu which they found astounding as you do not need this power when running these programs and this is just a waste of battery power.
What they found to be even more astounding was that when programs such as DVD-Player, Safari and iTunes as well as Adobe Lightrooms are started it only run with the lesser graphics chip (the Intel HD).
When you play videos on YouTube they say that here too only the Intel chip is activated when you use Safari or Firefox to watch these videos and only Googles Chrome actually allows the graphic chip to switch to the Nividia graphics.
They say it seems that the Mac uses the API`s to decide which program needs which chip to perform with. As soon as a program runs that the Mac feels needs the higher horse power it switches. They are however of the opinion that the Mac sometimes makes the wrong decision and this can negatively effect either the battery run time or the program graphics.
In conclusion this magazine says that Apple has made the use of this new system very easy to use (it does so automatically and the user cannot influence it)) but unfortunately it does not seem to work as it should and they hope that Apple will quickly find a solution for this problem.
I hope this helps somewhat to understand the issue.
Personally I do not like the way Apple is going with this. I do not want the machine to make such decisions for me. I want to be able to choose which graphic chip I use and when, and not have it done automatically. At least I should have the choice of setting the system on auto or manual.
