My brother put me on to an article by a Dr. Terry Mortenson that highlights Jesus' perspective on the age of the earth. The article focuses on 3 Gospel passages, explains them, and then surveys 61 scholars--theologians, commentators, etc.--as to how they interact (or fail to) with these texts.
"But at the beginning of creation God ‘made them male and female.’" Mark 10:6 (NIV)
"because those will be days of distress unequaled from the beginning, when God created the world, until now—and never to be equaled again." Mark 13:19 (NIV)
"Therefore this generation will be held responsible for the blood of all the prophets that has been shed since the beginning of the world, from the blood of Abel to the blood of Zechariah, who was killed between the altar and the sanctuary. Yes, I tell you, this generation will be held responsible for it all." Luke 11:50-51 (NIV)
While in each case, Jesus' main point wasn't the age of the earth, yet nevertheless his understanding (and we note that his understanding was/is flawless) was that "man has existed essentially as long as the entire cosmos has" (Mortenson, p. 7).
Thus do these verses seem powerful evidence that Jesus believed the earth to be significantly younger than many biblical scholars (many of whom I respect) do today.
Jesus would know. After all, not only is he God (Jn 1:1), he was with the Father in the beginning (Jn 1:2), and he created the earth (Jn 1:3).