It's more big news in the world of health insurance—and potentially for the wallets of consumers—though this time it doesn't revolve around the fate of ObamaCare. The Wall Street Journal reports that CVS has offered to buy giant insurer Aetna for $66 billion. Why? One big reason is a familiar one: fear of the behemoth Amazon. Here's a look at the details, including the potential implications for customers if the deal goes through: