You may not have noticed, but last week a number of extensions were released to the Visual Studio Gallery to support VS/TFS 2013 RC:
There aren't necessarily any new features in these updates, but they do support 2013 RC for all the items you know and love, like the Best Practices Analyzer, Check-in policies, Process Template Editor, TFPT, and more.
And don’t forget to take advantage of the MSSCCI providers to allow integration with TFS from a myriad of other environments, such as VS 2005, VB6 (yup!), SSMS, PowerBuilder, and other SCCI-compliant IDE’s.
Enjoy the rest of your Tuesday!