No, the earth is oblate because of angular momentum.
What he's saying is that the ocean's surface is lumpy because of local gravitational affects (one reason why we talk about mean sea level). The Greenland ice cap is a great mass and so it exerts a gravitational pull on the ocean around it, causing the ocean to bulge up around Greenland. If the ice were to melt away the bulge due to the icecap's mass would go away.
What he's saying is that the ocean's surface is lumpy because of local gravitational affects (one reason why we talk about mean sea level). The Greenland ice cap is a great mass and so it exerts a gravitational pull on the ocean around it, causing the ocean to bulge up around Greenland. If the ice were to melt away the bulge due to the icecap's mass would go away.