After an 11-month absence, General Motors (NYSE: GM) is advertising on Facebook (NASDAQ: FB) again.

According to AdAge, Chevrolet is rolling out a mobile advertising campaign for the Chevy Sonic on the leading social networking website.

It's about time for GM to come back after embarrassing Facebook shortly before its IPO by vocally bowing out as an online advertiser. Did GM really think that its marketing dollars would be better spent on old-school media, sidestepping the sticky social site that attracts more than a billion active users worldwide?

In this video, Rick explains why GM returning as a sponsor is so important to Facebook even if the financial sums may be insignificant. GM's back in Facebook's garage, but it never should've left in the first place.

Longtime Fool contributor Rick Munarriz has no position in any stocks mentioned. The Motley Fool recommends and owns shares of Facebook. It also recommends General Motors. 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.