If you're dealing with a version of SQL Server greater than SQL Server 2000, at this point I'm going to say yes. The reason I say yes is looking at the files that are updated. For instance:
What is clear is that it's more than just SSRS specific files being updated. Therefore, it looks like it is best to patch all installs of SQL Server 2005-2012. SQL Server 2000 Reporting Services was a stand alone component, so I don't believe this should affect anything other than specifically SQL Server 2000 Reporting Services.