Since hitting an all-time high several weeks ago, Apple's stock has gone through a turbulent patch. Investors meanwhile, are considering several issues that could dramatically impact the tech giant's future direction.

Warner Brothers' The Dark Knight is the first flick to be offered directly via the social network. It's a small test, but when Facebook enters a business, competitors get nervous: Here's how this move could trigger a round of mergers among Netflix and other established players.

To get a better idea how Apple might fare without Steve Jobs's leadership, it's helpful to look at another hugely successful American company that decades ago lost its iconic CEO -- Walt Disney Co. After Walt passed away in 1966, his company didn't miss a step -- at least not for several years.

After a long, painful transformation from an online auction site to a mobile-focused e-commerce hub, eBay is finally staging a comeback, online and on Wall Street. But auction sales don't account for its rousing recovery. For that, it has PayPal to thank.

Yes, we've seen this movie before: As costly oil makes solar look good, investors pile in -- only to be let down when overcapacity sets in and oil prices tumble again. But this time, solar's rebound may be on somewhat firmer ground. Investors, though, still need to be cautious.

Cisco's latest earnings topped analysts' estimates, but profit margins disappointed investors, and the stock plunged 15%. CEO John Chambers insists it's only temporary and that better days are coming. So far, though, nobody is buying that line.

From a strategy standpoint, there's some sound reasoning behind CEO Stephen Elop's thinking: Most likely there's room for a third player at Apple and Google's poker table. But Nokia's new deal with Microsoft will be all about how well it's executed.

The online retail giant functions like two stocks: One is speculative and volatile, with unusually high valuations -- and high demands for returns. The other is for long-term investors, who get rewarded for buying and holding with capital gains and consistent growth.

Investors are buying into the meme that Windows is dying -- and therefore Microsoft is as well. While tablets are clearly cutting into the giant's core PC business, Microsoft is also showing remarkable agility in building new franchises for the future, the Kinect for one.

As Larry Page takes the reins from CEO Eric Schmidt, the questions for investors are: Will Facebook keep gaining on Google? Or will Page steer it back to its original counter-corporate spirit, embracing risk over short-term profits? Or have the risk-takers gone soft?