Visual Studio 2010 RC has just been released. While the setup process should be very straightforward, it may fail even if you follow the instructions step by step, which was my case. The log file showed the following error:
Microsoft Visual Studio 2010 Ultimate RC - ENU:  CRootComponent::Install(): Cannot install; setup files failed verification. Microsoft Visual Studio 2010 Ultimate RC - ENU:  ERROR_INSTALL_PACKAGE_INVALID returned in CRootComponent::Install; the following file is invalid: c:\xxx\vs 2010 rc install\vs_setup.msi VS70pgui:  DepCheck indicates Microsoft Visual Studio 2010 Ultimate RC - ENU is not installed.
I tried several times and removed a few programs from Control Panel, and was able to complete the setup. Note that these steps below are neither prescriptive nor complete.