Visual Studio 2013 Preview was made available for download in the
last few days and it is very good indeed. However, I need ReSharper 
in my IDE.
The current installer (8.0.9.1171) does not appear to support VS 
2013 as there is no option to to select it, however it does silently 
install into VS 2013. So install away and enjoy ReSharper in the 
new Visual Studio 2013 Preview.