I tried the Beta and the RC1. I ran into a screen "You are running ie with accelerators disabled" despite having chosen them. To try to fix this I was directed to "Live" to install it despite having it on my machine. Also, HP Web Print was offered and when chosen I was redirected to HP and despite enabling it, ie8 con't to show error mesages.
Uninstalled it. ie7 runs just fine. I use Opera for almost everything now since FF3 turned slow.