Providing yet another reminder of how interconnected global markets are, U.S. stocks advanced today on news of a proposed $1.4 trillion injection into Japan's economy by the country's central bank. This is notable because the move nearly doubles Japan's monetary base by the end of next year. As a result, Wall Street is optimistic that the stimulus can help Japan emerge from 20 years of minimal growth. The Dow Jones Industrial Average (DJINDICES:^DJI) which added 55 points, or 0.4%, also saw a few big-time announcements from its components, and ended the day at 14,606.

Rebounding from a steep decline in the prior three trading days, Hewlett-Packard (NYSE:HPQ) shares rose 1.8% today to lead the index. HP had fallen in recent days on analyst sentiment that the stock was overvalued after a huge run-up in 2013 -- its meteoric 56% rise this year still tops the index by far. The biggest news from HP actually came after the markets closed: the chairman of HP's board, Raymond Lane, is giving up his leadership position. Two other board members are resigning, making for an uncertain future at the top of the company. 

International Business Machines (NYSE:IBM) slipped 0.6%, to end as one of the weakest blue chips today. Its decline, though hardly extreme and not substantiated by any major revelations, comes as Big Blue defends itself against claims from rival server manufacturer Oracle (NASDAQ: ORCL). IBM rushed to combat various assertions from Oracle that IBM's server offerings are slower than Oracle's, claiming that the comparisons used outdated IBM products.

But, by far, the biggest news out of the Dow today came from AT&T (NYSE:T). Taking the stage with Facebook's (NASDAQ:FB) Mark Zuckerberg, AT&T Mobility CEO Ralph de la Vega excitedly announced that AT&T would be the exclusive service provider on the new HTC First smartphone. The First will indeed be the first smartphone that's built with Facebook's new Home interface to hit the markets, and could be a big win for the service provider. For Facebook, today marked a new era in the company's quest to integrate social media with mobile devices.

Fool contributor John Divine has no position in any stocks mentioned. You can follow him on Twitter @divinebizkid and on Motley Fool CAPS @TMFDivine.

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