One of the greatest features of Team Foundation Server is it's extensibility via the TFS Object Model. A short while back I received a question asking how to retrieve a list of all files included in all the changesets associated with a build. The intent (of the person asking the question) was to deploy only those files that had been modified in one of the changesets.
The following code example is what I came up with. I can't say it's the only way, or even the most efficient way, to achieve the desired result, but it's at least one way :-) I've also posted this example on TFSExamples.com, here.