Just installed with clean install using official Windows 8 (RTM) image distributed by my office. The 10GB image was distributed using custom built deployment app that downloads the image from Windows Azure from server locations nearest to us. Download took about 3 hours from my home network.
Overall install process took me about 1 hour, as all required configuration and applications has been pre-configured. The steps that I need to do was only changing keyboard layout, regional setting, and the join domain (automated via VPN since i'm out of office network).
Best part is, I don't need to do Easy Transfer to backup my files initially (although I did, for backup purpose), as the Windows installation will move our old profile into "\Windows.old" folder. Hard part is to move the files that I need to the new profile that I have.
Pretty sleek UI. Still getting used to the gestures.
Next step: installing Office 2013. To be continued...