I'm looking into improving our build and release system. We are a .Net/Windows shop, and I don't see any really good tools for Windows for generating the files that are to be dropped in patch or hotfix. We are currently using TFSBuild 2010 with Windows Workflows for our continuous integration builds as well as our daily full build which includes an Installshield package for deployment.

1. What is a good way of generating the list of files to be included in a "patch" style release, where one does not redistribute all the files, but only those necessary to accomplish the necessary changes? Are there any open source tools that work well for this, or do teams usually roll their own? I have considered using Beyond Compare but I would prefer something open source. The file "patch" creation must be 100% automatable.
2. Which release vehicles really ought to be patch style? And which releases should replace all system files related to our application? Assume we have a very large amount of resources necessary to maintain.
3. Is there any established material that is trusted within the industry for strategies about this? I realize it is different for "enterprise" rather than with typical websites. I am looking more for "enterprise" strategies due to our product distribution style.

tl;dr > Looking for info on how to ship more reliable packages?