Submission + - Windows 8 Developer Preview to be released later t (msdn.com)
Retron writes: Although various leaked versions of Windows 8 have been floating around the Net for the past few months, Microsoft will release an official developer preview later today. The options include x86, x64 and x64 with developer tools and sample applications, all in ISO format. Upgrades from Windows 7 aren't supported, so best to use a VM or spare partition.