Read original post by Mary Jo Foley at ZDNet
Microsoft will deliver Windows 8.1, codenamed "Blue" to OEMs in late August 2013, company officials said on July 8.
So it looks like Windows 8.1 is going to be released to manufacturing by August, after all, as tipsters have been saying since the Blue codename first leaked almost a year ago.
Microsoft delivered a public preview of Windows 8.1 on June 26 during its Build conference. There are no more preview/test builds scheduled. The next stop is RTM.