Rob Mensching has outlined some info on the targets for WiX v3. (http://robmensching.com/blog/archive/2007/04/10/WiX-v3-Roadmap-Draft.aspx) There's some good looking features in the roadmap. In particular I'm interested in the improved patch support and the expansion of ClickThrough support. The bootstrapper extensions sound good as well.

Congrats to the team for reaching the end of WiX v2.