Just when I thought I had closed out my blog for the year, I stumbled across a post in the MSBuild forum. Victor Chen is one of those forum monitors that knows his stuff inside and out. He happened to post a reply to someone about updating config files and I had forgotten this little gem was available in MSBuild. You can easily update files with something like this:
<FileUpdate Condition=” ‘$(Configuration)|$(Platform)’ == ‘Foo1|Foo2′”
Keep this in your toolkit. It could help you out in a pinch.