Ask any investor what they think about Johnson & Johnson (NYSE: JNJ ) , and you'll probably hear that it's a diversified pharma company, a blue-chip stock that pays a hefty dividend, and it's a relatively safe investment for investors looking for exposure to the health-care sector. But you might also hear investors criticize its size. With a market cap of almost $260 billion, Johnson & Johnson is one of the largest companies in the U.S., and it edges out both Merck and Pfizer as the largest pharma company in the Dow. Can a company this massive be nimble and entrepreneurial enough to innovate? Is its size holding back its long-term potential to bring new products to market?