It's a Starcraft themed parody of Justin Bieber's "Baby", done by youtube's popular starcraft caster HuskyStarcraft and youtube musician KurtHugoSchneider. It's pretty funny and the music, vocals and filming are all high quality. You should check it out
I've been subscribed to Husky for a while now. He's an entertaining caster and his channel is great if you like watching high level Starcraft game play.
I usually wouldn't post a link to youtube videos, but they announced that all the revenue generated from the video would be donated to charity. So click the link, it's for a cause!
Here are both their channels, though you can find out a lot more information by reading the video description.