Microsoft announced revenue of $12.92 billion for the first quarter ended Sept. 30, 2009, a 14% decline from the same period of the prior year. Operating income, net income and diluted earnings per share for the quarter were $4.48 billion, $3.57 billion and $0.40 per share, which represented declines of 25%, 18% and 17%, respectively, when compared with the prior year period.

These financial results reflect the deferral of $1.47 billion of revenue, an impact of $0.12 of diluted earnings per share, relating to the Windows 7 Upgrade Option program and sales of Windows 7 to OEMs and retailers before general availability. Adding back the deferred revenue, revenue totaled $14.39 billion, a 4% year-over-year decline, and EPS totaled $0.52 per share, an increase of 8% over the same period of the prior year.

“We are very pleased with our performance this quarter and particularly by the strong consumer demand for Windows,” said Chris Liddell, chief financial officer at Microsoft. “We also maintained our cost discipline, which allowed us to drive strong earnings performance despite continued tough overall economic conditions.”

Windows 7 and Windows Server 2008 R2 launched globally on Oct. 22 as anticipated. Also during October, Microsoft released Microsoft Exchange Server 2010 to manufacturing and in July announced a strategic partnership with Yahoo! Inc. to provide search results for their global properties.

“The worldwide launches of Windows 7, Exchange Server 2010 and Windows Server 2008 R2 are exciting milestones for Microsoft, our partners and customers,” said Kevin Turner, chief operating officer at Microsoft. “We are pleased by the early positive response we are receiving for these products.”

Microsoft is reducing operating expense guidance to $26.2 billion to $26.5 billion, for the full year ending June 30, 2010.