Pull up a seat if you want to hear about some new information regarding the RTM of Windows 8. Wzor, who has been known to leak Windows information in the past, has just updated a post that says Windows 8 RTM build will be 8500.0.120623-1707. We should note this contradicts Win8China's claim that the final build will be in the 8600 class.
Additionally, the source states that Microsoft will make the announcement in late July and says sometime between the 17-20. We should note that two Microsoft events happen during this timeframe. First, on the 19th, Microsoft has their earnings call and also there is the MGX, which runs from July 17-20; the source specifically states that it is coming at the MGX event.
This information lines up to previously released information that says Microsoft will finish the Windows 8 RTM build in July; it would appear that Windows 8 RTM is literally right around the corner.
Windows 8 has been noted to be Microsoft's biggest gamble yet. But, with the hardware/software that was just announced (Microsoft Surface and Windows Phone 8), the entire ecosystem around the platform is coming together. If true, July will be yet another busy month as the company takes one giant step towards Windows 8 retail availability.
Is it in the 8500 or 8600 class? That we do not know. But, there have now been several sources pointing towards a July sign-off which bodes well for the speculated October release date.
Thanks to @AngelWZR for the tip and translation!