eMarketer expects Facebook's (NASDAQ:FB) digital ad revenue to grow 37.6% this year, trumping Google's (NASDAQ:GOOGL) 18.6% estimate. Impressive, indeed. But as Fool contributor Daniel Sparks explains in the video below, valuation changes the story.

Fool contributor Daniel Sparks has no position in any stocks mentioned. The Motley Fool recommends Facebook and Google. The Motley Fool owns shares of Facebook and Google. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.