Microsoft on Thursday made its new Windows 7 operating system available to certain IT professionals, hardware manufacturers, and software developers.

Windows 7 screen shot
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Tech pros who subscribe to Microsoft's TechNet program can download the OS starting today, as can independent hardware vendors and independent software vendors.

Volume Licensing business customers with Software Assurance subscriptions can download Windows 7 starting Friday.

Microsoft is dribbling out Windows 7 to its industry partners and high-volume business customers weeks ahead of the product's Oct. 22 public debut to ensure that it's fully supported and bug-free by the time it hits store shelves or shows up on new computer models.

Gold or Certified members of Microsoft's Partner Program get access to Windows 7 on August 16, while Action Pack subscribers get the OS on August 23. Sept. 1 marks the day when Volume Licensing customers who do not have Software Assurance subscriptions can download the Release To Manufacturing, or final, version of Windows 7.

The full version of Windows 7 Home Premium is priced at $199, with an upgrade from Vista or XP costing $119. The full version of Windows 7 Professional is $299, with upgrades going for $199. Windows 7 Ultimate is priced at $319, with the upgrade version at $219.

Microsoft is hoping Windows 7's release kickstarts software sales. Vista, Windows 7's predecessor, proved unpopular with many consumers and was largely shunned by the corporate market for its intrusive security measures and incompatibility with older applicatios.

The company also cited an unfavorable mix of basic-to-premium sales as a factor when it reported that Windows sales plunged 29% in the most recent quarter.

Upgrading from XP to Windows 7? Here's a step-by-step guide.