Microsoft has been hard at work on builds of Windows 7 (post RTM) and Windows 8. While it is impossible to actually list every build compiled, we do have a list, from a reliable source of information that lists nearly all of the builds to date.
The information posted below comes from MDL who has a solid history of not only providing leaked information but also being accurate with their leaks as well. The list is broken down into Post Win 7 builds and Windows 8 builds. Windows 8 is broken down further into its milestone builds.
The list of builds represents Microsoft"s hard work towards completing the final product which has been rumored for both a January 2012 launch and a late 2012 launch. While there is more weight around a late 2012 launch some believe that the January 2012 launch may be with Windows 8 ARM based version for tablets.
Winmain Branch Post-RTM:
6.1.7650.0.winmain.090917-1843
6.1.7651.0.winmain.090924-1802
6.1.7656.0.winmain.091015-0833
6.1.7658.0.winmain.091019-1850
6.1.7659.0.winmain.091020-1830
6.1.7660.0.winmain.091021-1736
6.1.7661.0.winmain.091022-1755
6.1.7662.0.winmain.091023-1645
6.1.7664.0.winmain.091027-1825
6.1.7691.0.winmain.100106-1825
6.1.7692.0.winmain.100107-1735
6.1.7693.0.winmain.100111-1820
6.1.7694.0.winmain.100113-1753
6.1.7695.0.winmain.100114-1855
6.1.7696.0.winmain.100115-1725
6.1.7700.0.winmain.100122-1900
6.1.7702.0.winmain.100126-1751
6.1.7703.0.winmain.100127-1845
6.1.7704.0.winmain.100128-1900
6.1.7705.0.winmain.100129-1930
6.1.7706.0.winmain.100201-1820
6.1.7707.0.winmain.100202-1715
6.1.7709.0.winmain.100204-1515
6.1.7710.0.winmain.100205-2005
6.1.7711.0.winmain.100208-1732
6.1.7712.0.winmain.100211-1740
6.1.7713.0.winmain.100212-1750
6.1.7714.0.winmain.100215-1450
6.1.7715.0.winmain.100217-1715
6.1.7716.0.winmain.100218-1836
6.1.7717.0.winmain.100219-1707
6.1.7718.0.winmain.100223-1403
6.1.7719.0.winmain.100224-1231
6.1.7720.0.winmain.100225-1845
6.1.7721.0.winmain.100226-1832
6.1.7722.0.winmain.100301-1456
6.1.7723.0.winmain.100302-1805
6.1.7724.0.winmain.100303-1435
6.1.7725.0.winmain.100304-1545
6.1.7726.0.winmain.100311-1807
6.1.7727.0.winmain.100315-1740
6.1.7727.0.winmain.100315-1747
6.1.7729.0.winmain.100318-1855
6.1.7730.0.winmain.100319-1635
6.1.7731.0.winmain.100323-1817
6.1.7755.0.winmain.100525-1800
7764.0.100615-1748
Milestone 1
6.2.7800.0.winmain_win8m1.100816-1855
6.2.7804.0.winmain_win8m1.100820-1742
6.2.7809.0.winmain_win8m1.100827-1740
6.2.7811.0.winmain_win8m1.100831-1731
6.2.7812.0.winmain_win8m1.100901-1810
6.2.7814.0.winmain_win8m1.100903-1700
6.2.7817.0.winmain_win8m1.100910-1622
6.2.7818.0.winmain_win8m1.100913-1840
6.2.7821.0.winmain_win8m1.100916-1940
6.2.7821.0.winmain_win8m1.100916-1940
6.2.7822.0.winmain_win8m1.100920-1625
6.2.7853.0.winmain_win8m1.100928-1040
6.2.7855.0.winmain_win8m1.101001-1815
6.2.7857.0.winmain_win8m1.101006-1908
6.2.7859.0.winmain_win8m1.101008-1300
6.2.7866.0.winmain_win8m1.101019-1507
6.2.7867.0.winmain_win8m1.101020-1800 [ CES 2011 ]
6.2.7870.0.winmain_win8m1.101025-1900
6.2.7871.0.winmain_win8m1.101026-1800
6.2.7874.0.winmain_win8m1.101029-1838
6.2.7875.0.winmain_win8m1.101101-1832
6.2.7878.0.winmain_win8m1.101104-1752
6.2.7880.0.winmain_win8m1.101108-1530
6.2.7881.0.winmain_win8m1.101109-1816
6.2.7882.0.winmain_win8m1.101110-1650
6.2.7883.0.winmain_win8m1.101111-1631
6.2.7890.0.winmain_win8m1.101122-1810
6.2.7891.0.winmain_win8m1.101123-1908
6.2.7892.0.winmain_win8m1.101129-1902
6.2.7895.0.winmain_win8m1.101202-1845
6.2.7898.0.winmain_win8m1.101207-1620
6.2.7899.0.winmain_win8m1.101208-1900
Milestone 2
6.2.7900.0.winmain_win8m2.101209-1830
6.2.7901.0.winmain_win8m2.101210-1755
6.2.7902.0.winmain_win8m2.101213-1745
6.2.7903.0.winmain_win8m2.101215-2325
6.2.7904.0.winmain_win8m2.101216-1845
6.2.7905.0.winmain_win8m2.110103-2100
6.2.7906.0.winmain_win8m2.110105-1750
6.2.7907.0.winmain_win8m2.110106-1823
6.2.7907.0.fbl_x.110109-1800 (FBL)
6.2.7909.0.winmain_win8m2.110110-1515
6.2.7910.0.winmain_win8m2.110111-1804
6.2.7911.0.winmain_win8m2.110112-1725
6.2.7913.0.winmain_win8m2.110114-1745
6.2.7914.0.winmain_win8m2.110118-1605
6.2.7915.0.winmain_win8m2.110119-1806
6.2.7916.0.winmain_win8m2.110121-1715
7917.0.winmain_win8m2.110125-1757
6.2.7920.0.winmain_win8m2.110128-1740
6.2.7920.0.fbl_srv.110128-1823 (Notepad.exe)
6.2.7921.0.winmain_win8m2.110201-2005
6.2.7922.0.winmain_win8m2.110202-1840
6.2.7925.0.winmain_win8m2.110207-1736
6.2.7926.0.winmain_win8m2.110209-1755
6.2.7927.0.winmain_win8m2.110210-1740
6.2.7928.0.winmain_win8m2.110214-1825
7929.0.winmain_win8m2.110215-1802
6.2.7930.0.winmain_win8m2.110217-1825
6.2.7947.0.winmain_win8m2_escrow.110218-1608 latest build of Windows 8
Image Credit: clickonf5 (Flickr)