What’s the return on hundreds of thousands of likes and comments for brands spending big on Facebook ads? For General Motors, it’s simply not enough. Just two days before Facebook’s IPO, the automaker—which happens to be the third-largest advertiser in the country—has decided to pull its ads from Facebook. The move raises the question as to whether brand awareness and engagement via Facebook actually has dollars-and-cents value and therein, if Facebook’s business model—based heavily upon advertising—is even sustainable.

Conversely, GM could’ve very well acted far too soon. After all, Facebook’s biggest demographic, 18-24 year-olds, aren’t exactly out buying cars in droves given the current economic climate. Also, as one Ford exec told Reuters, “You can’t just buy your way into Facebook. You need to have a credible presence and be doing innovative things.”

[via Reuters]