The rumors turned out to be true. Microsoft will release a public beta this week of its next desktop operating system, Windows 7, hoping it will address the problems that have made Windows Vista perhaps the least popular OS in its history.

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Microsoft CEO Steve Ballmer will launch the beta during his speech at the start of the Consumer Electronics Show in Las Vegas on Wednesday. It's Ballmer's first year giving the opening address, traditionally handled by former CEO Bill Gates. His blustery style is likely to contrast sharply with Gates' meek and thoughtful demeanor in years past.

Ballmer will also announce several partnerships that could help widen the use of Microsoft's Windows Live online services and applications. They include a deal with Dell to preload Windows Live Essentials and Live Search on all its PCs for consumers and small businesses starting in February, said Craig Beilinson, director of marketing for Microsoft's entertainment and devices division. Another deal will see Verizon preinstall Live Search on all its cell phones in the U.S. later in the first half of this year.

Microsoft's CEO will also announce a new Netflix application for Windows Mobile, due later this month, that lets people order movies and update their queue from their phone, and a new version of the Windows Mobile browser.

One thing Ballmer will not do is unveil a Zune mobile phone, Beilinson said, as some rumors had suggested. Nor will he rebrand Live Search with a catchy new monicker -- "Kumo" -- to help it better compete with Google, as others had predicted.

But he probably will spend a lot of time showing Windows 7. The OS is now "feature complete" and a new beta will be available for the general public to try out on Friday. Microsoft will cap the beta after about the first 2.5 million downloads. Microsoft developers, including MSDN, TechNet and TechBeta subscribers, will be able to download the beta Wednesday night, two days earlier than the general public, Beilinson said.

The minimum recommended hardware for the beta includes a 1GHz processor, 1GB of system memory, 16GB of available disk space and support for DX9 graphics with 128MB of memory (to enable the Aero theme), Microsoft said. The recommendations may change for the final product, it said.

The IDG News Service is a Network World affiliate.