I'm just starting out with WiX as I need to be able to automate building an MSI on our CI server. Is there anyway to automatically include all the dependencies of a project?
The "proj" extension to heat.exe is getting better. Heat isn't quite ready to be used for production in an automated fashion. It's a very reasonable way to get the initial structure put together but doesn't quite do the right thing with repeated runs (for example, Component/@Guids aren't stable, yet...).
When the above issues are solved in heat.exe then incorporating it into your build process will certainly save all the trouble that people mention above. It's on our list to do better after the most egregious bugs are fixed in the core toolset.