Will be released on MSDN, TechNet, and oem.microsoft.com later today (4/21)
Will be released to Windows/Microsoft Update (update.microsoft.com) and Microsoft Downloads (microsoft.com/downloads) on 4/29.
Will be "Pushed" to computers with automatic updating on starting 6/10.
I'm reinstalling today (an HP printer driver screwed up a whole svchost tree and my PC needs the reinstall anyways), so we'll see how it is after a slipstream.