For the first time in a long time, Detroit is gaining ground: Ford (NYSE:F), General Motors (NYSE:GM), and Chrysler all posted gains in U.S. market share in the first quarter, with sales growth that outpaced the overall market.

What's going on? In this video, Fool.com contributor John Rosevear explains how it's all about the product – and also about some economic trends that especially favor Detroit's Big Three right now.