According to Russian site MSWin.Me, Windows 8 beta may be released between July 14th and the 28th. While this is just a rumor, it may have some merit. The previous rumor was that Microsoft was going to release the Community Technology Preview at the 2011 Microsoft Worldwide Partner Conference in Los Angeles, California in July.
As mentioned earlier, Microsoft at the end of June was to gather the community technology preview (CTP) version of Windows 8 to demonstrate (and, possibly, to "test drive") to its partners at the Conference, WPC2011, to be held in Los Angeles from 10 to 14 July. Information about whether the established this Assembly, we do not have, but there is something more meaningful: one of the team members, WZor.net has shared information about what Windows 8 beta, according to their sources, collected between 14 and 28 July.