Forget Build 7057, Microsoft has already moved the development process of the next iteration of the Windows client past the latest leaked test release from the RC-branch available in the wild. A superseding interim build of Windows 7 from the Release Candidate branch, namely 7061, already shipped to the company's close partners and select testers. At the same time, the software giant has updated its Technology Adoption Program for Windows Vista's successor indicating that it will move the operating system into RC-Escrow next month and that it will produce the first fully fledged Release Candidate milestone in just a couple of months.

Initially Microsoft had informed members of the TAP program that it was planning to make Windows 7 RC available in April 2009, according to a leaked product roadmap courtesy of Lotta Bath, from the Microsoft Sweden Partner team. Wzor (via Neowin) is reporting that the Redmond company has updated this schedule, and that Windows 7 will enter RC-Escrow in the last week of April, while the fully fledged Release Candidate is planned for availability by the end of May 2009 (also the last week).

Microsoft of course, has yet to confirm or deny any leaked details related to the development process of Windows 7 past Beta Build 7000, which was offered as a public download on January 10, 2009. By discussing the changes integrated into post-Beta Windows 7 development milestones, the software giant managed however to offer confirmation of the validity of Builds 7048 and 7057 leaked to torrent websites.

At this point in time, Steven Sinofsky, senior vice president, Windows and Windows Live Engineering Group, indicates that Microsoft continues to gather feedback and telemetry from people running Windows 7 Build 7000. No word on Windows 7 Build 7061, which is reportedly out, having been compiled on March 11, 2009. No word on the build number that will end up as the official Windows 7 Release Candidate either. Still, until the RC, Microsoft has to go through RC-Escrow, a development milestone synonymous with a focus on detecting show-stopping bugs and regression issues, while confirming that all reported bugs have been dealt with.

Windows 7 Build 7057, labeled Release Candidate 1, is nothing short of a fresh leak, having made it into the wild an on BitTorrent trackers just the past week. You will be able to see the complete installation experience here and to access over 100 screenshots of Windows 7 Build 7057 via this link, in order to get an idea of the changes implemented since Beta Build 7000.