Now that Windows XP SP3 RC is out of the way, get ready for the first Release Candidate of Windows Vista SP1, as soon as next week. The synchronization of the updates for Windows Vista and Windows XP is not a model of accuracy as far as Microsoft's service pack releases are concerned, but the company is not that far off as you might think. Ever since mid July, when the first preview Beta builds of Vista SP1 and XP SP3 were dropped in the laps of exclusive pools of testers, the development milestones of the two service packs are almost joined at the hip. Stepping into Beta and Release Candidate stages together, Vista SP1 and XP SP3 are even pointing to a concomitant launch in the first quarter of 2008, a scenario that remains unconfirmed by Microsoft.

In the mid of November, Microsoft made available the first Release Candidate for Windows XP Service Pack 3 and a preview of the Release Candidate for Windows Vista Service Pack 1. Both development milestones of Vista SP1 and XP SP3 were synonymous with Microsoft opening up the Beta program, and expanding the number of testers from 12,000 to some 15,000. Windows XP Build 2600.xpsp.071030-1537: Service Pack 3, v.3244, the fully fledged RC for XP SP3 accompanied Vista SP1 RC Preview Build's launch on November 14. XP SP3 RC was subsequently leaked to peer-to-peer file sharing networks. On top of this a hack was made available permitting all XP users to access the Release Candidate of the third and last service pack for XP.

In this first week of December, Microsoft is reported to make available the first RC of Vista SP1. At this point in time, according to Mary Jo Foley, the Redmond company is dogfooding an internal version of Vista SP1 RC build 17051. Microsoft still failed in disclosing its plans as to when it will deliver Vista SP1 RC via MSDN or to the general public. The final version of the service pack is still scheduled for the first quarter of 2008 with no additional details, yet.