Hewlett-Packard completed its $1.2 billion acquisition of Palm today, creating an interesting new challenger in the smartphone and tablet markets.

With Palm, HP gets control of its own operating system at a time when other tech giants are also becoming more vertically oriented. Microsoft and Oracle have been launching their own hardware; Intel has acquired or built operating systems; and Apple is ruling in smartphones because it makes everything from chips to the iOS operating system.

Palm’s webOS software will likely become the heart of HP’s upcoming smartphones and tablet computers. That’s a loss for Microsoft, since HP had been planning to build a tablet computer using Windows 7, and HP was reportedly working on a Windows Phone 7 smartphone as well.

The question is whether HP is too late to the party, or if the market is just getting started. Palm’s Jon Rubinstein, former chief executive and chairman of Palm, will run the Palm global business division at HP, reporting to former Palm CEO and current HP executive vice president Todd Bradley, who runs the Personal Systems Group at HP.

“With webOS, HP will deliver its customers a unique and compelling experience across smartphones and other mobility products,” said Bradley in a statement. “This allows us the opportunity to fully engage in growing our smartphone family offering and the footprint of webOS.”

Rubinstein said the deal will accelerate the development of Palm’s platform, giving it new resources, scale, and the support of a respected global brand. As for Palm, it’s the end of an era of independent innovation that began in 1992. Palm started in the handheld organizer business and pivoted into smartphones. Now it is moving into tablets. It will be interesting to see where HP goes next with its new operating system.

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