This is broad scenario...and tough to answer exactly. I would do appropriate branching and automate the processes as much as possible. Part IV: Large Project Considerations of the guide "Team Development with Visual Studio Team Foundation Server" addresses similar issue and available as (free) download at http://tfsguide.codeplex.com/
As per this scenario, you would find below presentation very helpful: http://channel9.msdn.com/Events/TechDays/Techdays-2013-the-Netherlands/From-Continuous-Integration-to-Continuous-Delivery-with-Visual-Studio-Team-Foundation-Server-2012
Hope those resources will help you to take informed decisions. Thanks.