Windows XP Service Pack 3, Windows Vista Service Pack 1 and Windows 7 are by all means not on the market yet, with some closer than others to becoming available to the general public. And yet the three operating systems are already in the same boat together. The same cannot be said about Vista gold and XP SP3 that are currently splitting Windows' install base among them, enjoying together the lion's share of the operating system market. Still, the three platforms are connected by more than just the Windows umbrella brand. As a matter of fact, all three products have been tested for antitrust flavors.

Vista SP1 was released to manufacturing on February 4, 2008, and subsequently shipped for the production of DVDs to OEM partners, to the 15,000 testers of the Beta program, to Volume License customers, and to MSDN and TechNet Plus subscribers. At the same time, XP SP3 is still in development, having hit the Release Candidate stage following the RTM of Vista SP1. As far as Vista's successor is concerned, in January, Microsoft shipped an early build to its key partners, and some information on Windows 7 Milestone 1 did manage to find its way to the public.

And yet XP SP3, Vista SP1 and Windows 7 have been reviewed by antitrust regulators. The next iteration of Windows as well as the two service packs were test driven ahead of release for compliance with the 2002 U.S. antitrust settlement by the Technical Committee.

"Plaintiff States and the TC continue to monitor developments regarding Windows XP and Windows Vista to assure compliance with the Final Judgments. This includes ongoing testing by the TC of the final versions of Windows Vista, Vista Service Pack ('SP') 1, XP SP 3, Windows Media Player 11, and Internet Explorer 7, to discover any remaining middleware-related issues," reveals an excerpt of the last joint-status report published for the Microsoft-Department of Justice case.

"As noted in the prior status report, as the scheduled expiration of the relevant portions of the Final Judgment approached, the TC identified a number of remaining middleware-related bugs and requested that Microsoft address these issues. Microsoft has corrected most of these issues, and the TC has tested the fixes. Microsoft has included these corrections in XP SP 3 or Vista SP 1, as appropriate. A remaining bug in the 'Open With' feature will be corrected in 'Windows 7,' the announced successor to Windows Vista. The TC and Microsoft continue to discuss another middleware issue, which the TC has sought to have Microsoft include in Windows 7," it is added in the report.

The Technical Committee has already dealt with the evaluation of Vista SP1 which is scheduled for general availability by mid-March, and XP SP3 which is still officially planned for mid-2008. At the same time, a build of Windows 7 has been submitted "recently" to the Technical Committee for review. Microsoft is currently working its way from Windows 7 M1 to Windows 7 M2.