Here's some details on my experiment to install Windows Vista Beta 2 on the Samsung Q1. All in all it worked pretty well, but I couldn't get the resolution changer to work and that is a deal breaker. And anyway, the main point was to see how well the drivers and other applications would work at the moment.

I would've loved to test Vista's SuperFetch and ReadyBoost to see if they help with battery life by putting in a CF card as extra "memory" as this might minimize hard drive activity and save some power. Can't wait for the hybrid drives (ReadyDrive in marketing speak) to be priced reasonably and widely available.

As for the speed it's hard to say. I've installed Vista on a couple of machines now and after the installation it seems to run a search index update or something since it tends to use the hard disk pretty heavily right after setup. I don't know how much of this is psychological. A busily flashing HD is so heavily associated with bad performance, even though it might not really affect it (Vista has a new "prioritized I/O" system that lets things like Defrag and indexer run at a lower priority in the background).

For those who want to travel down this road, here's how to get there:

• Reserve lots of spare time
• You’ll need an external DVD drive
• Create a backup, preferably an image of some sort
• Install Windows Vista
• Install pretty much all the drivers from the DVD or download them from Samsung's website
• Some application/driver installations will fail on the first attempt but Vista will kindly offer to "correct the problem" and it works! 

What works

• Wireless
• Menu button (+ volume to adjust brightness), volume buttons
• Touchscreen drivers and calibration (4 point tested)
• Intel Chipset drivers: Let windows "correct the problem with recommended settings". It will run the installation again and it will work.
• Bluetooth. At least partially. I got the ThinkOutside Stowaway Bluetooth keyboard paired up, but I got lots of requests for BT drivers such as audio, HID, Network etc. and didn’t test any other devices. When prompted for the missing drivers, browse to C:\Program Files\WIDCOMM\Bluetooth Software.
• Screen rotation at native resolution with Samsung's display drivers

Unknown/Untested

• Wired LAN
• CompactFlash
• Native TabletPC stuff? Not recognized as a tablet? The customized handwriting recognition option was disabled and it had a warning stating that it is only available on TabletPCs.
• Calibrating ClearType for the uncommon screen type seems to require fiddling with the registry. Since Vista uses ClearType by default everything looks a little blurry until you do this.

What doesn't work

• Can't upgrade from TabletPC 2005 to Vista. Have to do a clean installation (or dual boot?)
• Autorun setup program on the Q1 driver CD, though this gave the same errors on my desktop, too.
• Resolution changer (button).
• DialKeys: Has a hardcoded check for the operating system.
• Program Launcher: Has a hardcoded check for the operating system.
• Aero Glass. Looks like this will never be supported on the Q1.
• Brightness setting in the Mobilty Center (use the Menu button).

Incomplete list of things you should install from the driver CD

• Chipset driver
• Display adapter driver. I couldn't get the one from the CD/Samsung's website to work properly at first. Downloading a generic version from Intel seemed to work, but didn't give me the resolution changing.
• Touchscreen driver
• Sound driver
• Bluetooth driver (lots of clicking on "Allow install" here)
• Display Manager (Required by MagicKeys to actually do something)
• MagicKeys (enables hardware buttons)