We've been encouraged to install Vista at work for quite some time, but I measure how difficult it'll be for most people to use based on what happens at home.
I bought my personal copy of Vista Ultimate about a week ago, and just got around to installing it yesterday. I have to say, kudo's to the Windows team for the easiest installation I've EVER had, and my fastest installation since I was putting DOS on PC's 15 years ago.
I had been running a hardware RAID mirror, so I removed one of the drives and then booted from the Vista Ultimate DVD. Within five minutes I was able to delete my remaining drive's partitions and create a new single partition. Vista wouldn't let me install on this drive, citing 'potential incompatibilities.' I booted into the Fatal1ty A8N-SLI's BIOS and disabled the hardware RAID, then booted from CD again. This time setup was happy.
The setup experience from here on in was amazing. To go from a blank partition to booting into Vista took less than half an hour, and perhaps two or three minutes of my time, all at the beginning. After booting into Vista and starting to play, it found drivers enabling ALL of my hardware to work. This impressed me because I've got, among other things, a USB microphone, USB smartcard reader, third party PCI USB card, 7800 GT display with multimon, Hauppauge PVR-150 TV adapter, USB remote control, gigabit network, and lots of other goodies. It found drivers for *everything*, even a legacy driver for my built-in Realtek audio, and it did it without me having to lift a single finger.
Will I like Vista? That remains to be seen. But I can't say a single bad thing about installation. In a word, AWESOME.
Now it's time to buy three 500 GB SATA drives and set up a software RAID5 :)