Windows 7 SP1 has leaked and is worming it way through Torrent sites now for those that fancy a fiddle.
The build is recent - March 27th - according to Geeksmack which stumbled across the code. They report that the full build string is: 6.1.7601.16537.amd64fre.win7.100327-0053.
Doesn't that sound good? Notice AMD64 gets a mention.
There's not much yet about what the pack actually does.
Maybe we'll have a fiddle, too.