My daughter is a redhead, so many people have approached me to tell me redheads are dieing out. Red hair is a double-recessive trait, so both parents must carry the gene in order for their children to be redheaded. Knowing both my dad and Abel have red hair, we were well aware that Isabella had a 50% chance of being redheaded. We were so certain were were having a redhead baby that had she not been born on Christmas, her middle name would have been Rose.
In doing some research on the redhead gene, National Geographic did in fact do a study which reported that approximatly 2% of the world's population is gingy. By 2060, they estimated the gene may be nearly wiped out. Scotland has the highest population of gingys, with 40% of people carrying the gene and 12% are actually redheaded. In looking at this, I think we may see the gene lay dormant, but it would take many generations before it is actually wiped out in its entirety. The gene tends to skip generations due to its double-recessive nature, so I think we may see it pop up here and again.
From an evolutionary standpoint, the redhead gene had the beneficial effect of increasing the body's ability to make vitamin D from sunlight. This might be especially helpful if you lived in Alaska or Antartica, however, (living in California) today's carriers have an increased risk fo skin cancer and sensativity to temperature. I would think this would lead to a slightly lower rate of depression in redheads versus the rest of the population since a lack of vitamin D from sunlight has been shown to lead to certian types of depression.
In summary, redheads are not dieing out (I'm sure many will live past 2060), but the gene itself is becoming less prevalent. You may see fewer and fewer redheaded babies, but as long as color comes in a box, you'll always see redheaded adults.