Well I finally got my ROMS to show up in 'My Computer' and work okay, but still no luck with my soundcard or HP 3-in-one. Have sent off reports to MS with the relevant log entries and files, etc, so hopefully they'll find an answer for the release candidate, full version. I suppose that's all we can do for now...continue to send feedback and error reports.
Still, Vista is an exciting OS and I'm confident MS will iron out the bugs over time, with beta testers assistance, that is. Seems to me, MS is bending over backwards to assist with issues...so far I've received 11 emails from MS (Oz and US) to enquire about the problems I'm experiencing, offering assistance wherever possible.