You might wonder if WiX is already mature enough for the installation of large, complex applications with a large number of files to be deployed. Well, Microsoft itself is switching to WiX with all its major software packages. Just as an example, the setup of Microsoft Office 2007 was developed entirely with WiX.
That is a great testimonial to the maturity of WiX. The only problem is that it isn't true. Consider the following dialog:
This dialog is not created by WiX. It's created by an internally developed bootstrapper that provides a multilingual external user interface. Sure, the installers are mostly WiX underneath the covers ( I see some custom actions in there ) but the majority of the user experience has nothing to do with WiX. Additionally the Office 2007 consists of many smaller MSI's that are chained together. WiX simply does not yet support this story.
Sure, the WiX team is currently been working on Burn but it isn't done and the claim isn't true. Why is this important? Because I want everyone to remember, Don't Believe Everything You Read. I like WiX but let's keep it real and not get blinded by enthusiasm.