I can not even find an irc channel for it yet, so I was pretty excited to see a post about it on this forum.
Try the qt mailing lists, specifically 'automotive'.

so I feel that for the project to be successful it would need a strong developer community behind it.
To my knowledge at the moment it is mostly developed with backing of the automotive industry (and to my knowledge they are the only real users so far), yet the code it self is opensource - allowing anyone to contribute.

Would you recommend it as a way of developing applications for kiosks, HMI replacements or other industrial applications where critical function needs to be separated from additional features?
Yes - this is basically what the appman is for.