IIRC - the real difference between red and green is when they are harvested.
Correct. Red chilis are "ripe", while the green are still maturing.
Now, Mr. wharris2, you're right about habaneros. But for me, I prefer flavor with my heat; it is my nsHO that Hab's are hot for hot sake, and add basically no flavor to a dish. New Mexican chilis, on the other hand, be they red or green, have a flavor all their own, and add both taste and heat to a dish. They may not be as hot as a Hab (actually, very little else in this world is), but I'll take the flavor of a Middle Rio Grande chili ANYTIME!