Report Builder is an awesome tool in lieu of using Microsoft Office Excel or Business Intelligence Studio to create custom reports with SQL Server 2008 Reporting Services. The version of Report Builder that shipped with SQL Server 2008 is Report Builder 1.0. Report Builder 2.0 was later released with plenty of new features and a better report writing experience.
The only issue though is that the most discoverable way to install Report Builder using Click-Once is through Report Manager but it points to Report Builder 1.0 even after you install Service Pack 1 for SQL Server 2008.
If you installed Service Pack 1 for your Reporting Services instance, there is actually a way to change the behavior though to point it to the Report Builder 2.0 Click-Once install. Click “Site Settings” in the upper-right hand corner and then fill out the Custom Report Builder Launch URL to “/ReportBuilder/ReportBuilder_2_0_0_0.application” if your server is setup in Native mode (which it should be if it is the RS instance for TFS) or “/_vti_bin/ReportBuilder/ReportBuilder_2_0_0_0.application” if it is in SharePoint Mode.
Alternately, if you want to download the full MSI installer you can over at Microsoft Downloads: http://www.microsoft.com/downloads/details.aspx?FamilyID=9f783224-9871-4eea-b1d5-f3140a253db6&displaylang=en. Thanks to the Reporting Services Team Blog for the handy information.