Would you ever consider creating XBAP applications even though Silverlight exists?

The FAQ on xbap.org says that they are used for creating heavyweight .NET applications specific to Windows, whereas Silverlight has the portability and and does not require the .NET Framework (although most systems have it installed anyway).
I seem to see Silverlight applications quite a bit but I have never run in to XBAPs.

Although there still seems to be a reason to use XBAPs, has anyone here made the transition to Silverlight, or should I say not made the transition to Silverlight?