A spreadsheet is available online, which R27, Canouna, Zukona, and Razziatore (see the Credits tab) are maintaining to keep us updated with the current builds of Windows 8. The spreadsheet is accurate so I can only assume the information is coming from a chain that leads all the way back to Redmond. It would be nice to see a date/time column to track the progress of the builds against time.
Windows 8 – Build List | R27 on Google Docs

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