Reflective color (like crayons or ink):
Green + Red = Brown
Transmitive color (light, like monitors, etc.):
Green + Red = Yellow
The difference is whether the person is used to working in web or print media.
As to CPUs with graphics cores...it's an idea that should have been proposed well before now, especially with graphics becoming an even more important part of computing. AMD is poised to actually make a coup in this arena, considering they have a much more robust bus topology (HyperTransport) and can devote a lot more bandwidth to a graphics core (and even dedicate memory specifically to the graphics core) just by adding in taps dedicated for that purpose.
You would see much better performance than what you currently see in the way of IGP products, not to mention the ability to upgrade not just the processor, but also graphics at some point in the future, just by replacing one part. I could see a lot of business potential in just this alone, especially as we see computers making more use of graphics cores (both in eye candy for operating systems and for high speed parallel processing).