For the third straight day, all three major indexes are trading essentially flat. As of 2:30 p.m., the Dow Jones Industrial Average (DJINDICES:^DJI) is up six points, or about 0.05%. Meanwhile, the S&P 500 is down a mere 0.15%, and the Nasdaq trails the others with a 0.25% loss. Volatility, as measured by the VIX (VOLATILITYINDICES:^VIX), is up more than 4% ahead of tomorrow's big options expiration.

On the Dow, the biggest headlines go to Wal-Mart (NYSE:WMT), which has announced it has joined competitor Target in no longer selling Amazon's (NASDAQ:AMZN) Kindle e-reader. This isn't an e-reader ban either; Wal-Mart will continue to sell Apple's iPad tablet, along with Barnes and Noble's Nook. Why? Because Amazon threatens to disrupt the big-box business model (sorry, B&N -- try as you may, you don't measure up).

Over time, Amazon will continue to encroach on the brick-and-mortar retailers' turf (especially as more shipping centers allow same-day delivery), and those retailers don't intend to accelerate their demise by selling customers a device that encourages them to shop elsewhere. Wal-Mart investors clearly agree with the move, as shares are trading up half a percent.

Off the Dow, it may seem like Starbucks is similarly encroaching on Green Mountain Coffee Roasters' (UNKNOWN:GMCR.DL) turf -- by expanding sales of its single-shot espresso machine from website-only to select retail outlets. Shares of Green Mountain are down 8% in response, but this seems like an overreaction. Starbucks' Verismo is not really a direct competitor to the well-known Keurig line. Sure, they both produce caffenated beverages, but they largely appeal to two different buyers. While Green Mountain certainly has significant challenges in front of it, Verismo won't have blood in its latte if Green Mountain fails.