Only a short time after the Beta 1 has been published reports about a Release Candidate appeared.
Release schedule of Windows 7 (Source)
The Beta 1 of Windows 7 has been available for a few days now and there are already rumors about the next step. Microsoft is said to have scheduled a Release Candidate for April 2009 says the website Wzor.net.
After this step the development of Windows 7 is supposed to be pushed so that OEMs can preinstall the operating system on their products by fall. Until Christmas the retail versions are said to hit the market. At this time, Windows 7 will be available in English, German, French, Spanish and Japanese. Additional languages are supposed to be released in a two weeks rhythm until all of the 34 versions are available.
Furthermore there are supposed to be more Builds of Windows 7. The builds 7015 and 7016 are supposed to represent the first steps towards the Release Candidate.