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General Motors' marketing head for North America told Ad Age that GM now spends 1 in 4 ad dollars online. But moving online is also a way to cut the total ad-budget denominator in that equation. The more efficient online ad market requires less spending. One analyst sums it up: "Everyone is fine-tuning ad budgets now, and by paring back the ad budget, you can cut out millions in a minute." Bonus stat in the article: 1/3 of the people who buy American brand autos don't use the Internet as part of the shopping process.