[UPDATE 9/26/13] TFS 2013 will include support for both TFS 2010 build agents and controllers and also TFS 2012 build agents and controllers.
One of the changes we made in TFS 2012 for Update 2 was to support TFS 2010 build agents and controllers. This provides several major benefits. The first is the obvious one of not having to upgrade your build agents and controllers when you upgrade your server to 2012. The second is that you don’t have to alter your custom build WF activities to be built with 2012. The third is that you will still be able to use Windows XP and Windows Server 2003 to run build agents and controllers – OSes that are not supported with the TFS 2012 release. This feature is available in the currently released CTP 4 of Update 2, and the final version of Update 2 will be available shortly.
Martin Hinshelwood, a Microsoft MVP, has written an extensive blog post about this feature.
Did you know that Visual Studio 2012 Update 2 supports 2010 Build Servers? Being able to connect TF Build 2010 Controllers to TFS 2012 is opening up upgrade paths for customers that are currently blocked from upgrading to TFS 2012.
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