More stars in the sky or grains of sand on Earth?

Here is a link to a fascinating article I read this evening. What number do you think is larger - the number of grains of sand on all the beaches on Earth or the number of all the stars in the sky?

http://www.npr.org/blogs/krulwich/2012/09/17/161096233/which-is-greater-the-number-of-sand-grains-on-earth-or-stars-in-the-sky