I finally found a link at http://www.joyofsetup.com/2013/09/13/getting-from-here-to-there-for-wix-v3-8/which says that WiX 3.8 with VS2013 integration will be available by Halloween (luckily Australians know what Halloween means thanks to *The Simpsons*). However I can't find any other evidence that this might actually happen, getting clear announcements on WiX isn't easy. They seem a bit apologetic due to delays caused by end of year holidays and Thanksgiving, but since when did holidays stop a programmer? (I do my best coding on holidays!)
As suggested, I had a quick for other IDEs over WiX, but they seem commercial or lagging behind. In any case I don't want yet another IDE. They claim V3.8 will have improved Votive<http://wixtoolset.org/documentation/manual/v3/votive/>, which a search reveals to be the VS2013 integration (I think, even that's vague). In VS2012 the integration of the project template, properties and build were very nice, however the only way to edit the wizard generated WiX source files was as plain xml. I wonder if there will be some kind of designer over the raw source, which is what WiX desperately needs. I know that creating a full designer experience over the complex WiX source files would be a huge job, but it's not beyond their developer community I would think. Greg K