Free copies of Windows Vista, Business or Ultimate Edition. This is Microsoft's way of saying thank you to the participants in the Windows Vista Technical Beta Program. Windows Vista has been released to manufacturing on November 8 and Microsoft has made the operating system available for download to MSDN subscribers starting today, November 17.

But if you have been involved in the beta testing process of Windows Vista, you may be in for a little surprise. A free copy of Windows Vista Business or Ultimate. There is only a small catch. Microsoft is conditioning the free copy of its operating system with the submission of at least a single bug during the testing period.

Unofficial reports reveal that some 20,000 beta testers participated in testing the operating system, but only those that meet Microsoft's conditions will receive a complimentary copy of Vista Business or Ultimate. Microsoft will send out notifications via email informing the beta testers of their selection of free downloads and then provide a product key with a one week time for activation.