Yesterday brought news that Microsoft is raising its dividend by over 20% and allocating $40B of its cash horde to buy back its own stock.

Rational stock market investors and business school graduates will probably applaud the move. Generally speaking, it is better for a company to give money back to shareholders through dividends or buybacks rather than spending it on uncertain initiatives with unknown paybacks. That is true in many industries and I’m sure we’ll see Microsoft stock move up as a result.

However, Microsoft isn’t in most industries, it’s a technology company. Technology companies are supposed to make bets on uncertain initiatives in the hope of producing exceptional returns. In consumer and enterprise software, consumer entertainment technology, Internet media and search, and consumer and enterprise communication (and mobile phones and software), the world is changing rapidly. Competition is coming, and coming hard. And many of Microsoft’s emerging businesses, like Skype, Bing, Windows Mobile and Xbox are not dominant and could use additional investment or influx of talent from acquisitions.

By moving forward with the buyback, Microsoft seems to be signaling that it does not intend to invest further in these businesses, nor does it want to acquire large technology companies to pursue new talent, new technologies, or new ideas in order to stake a leadership position in an emerging area. (To be fair, Microsoft will still have billions available for acquisitions of smaller innovators). The company has been playing catch up in mobile, in search, in SaaS, and in consumer platforms like tablets.

The combined buyback/dividend raise seems to me like a very strong signal that they won’t invest internally NOR will they invest externally. While the PC isn’t going completely away, and Windows and Office will continue to generate substantial cash flow, it seems quite clear that Microsoft isn’t sure how to pursue dominance in any of these emerging areas. While they did just spend $7B to get Nokia’s mobile business, I’m not sure exactly what they got for it.