Omea Reader 2.1.1 (free version) installs and runs well under Vista Beta 2. I've discovered one quirk (design flaw?) though. I've set up a separate Data partition to make things easier dual-booting between XP and Vista. So after installing Omea under Vista, I hunted around for the settings on the XP install, found them under C:\Documents and Settings\{username}\Local Settings\Application Data\JetBrains\Omea and copied them over to the Data partition (e.g. F:\Omea). When I launch Omea under Vista and go to Tools | Options | Omea | Paths and set the database and log files path to F:\Omea it only accepts the new value for the Log Files. The database setting reverts to the standard Vista location E:\Users\{username}\AppData\Local\JetBrains\Omea. Seems like a bug or perhaps a design flaw?
For the record, after exiting Omea and copying over the settings to E:\Users\{username}\AppData\Local\JetBrains\Omea, replacing what's there, then restarting you'll find all your feeds, subscriptions, clippings, etc. are there which was a nice thing. Now the problem is remembering which OS I can run Omea in so I don't lose any data!
I wonder if there's a registry or file hack where the value is stored for the database path? Hmmm...
UPDATE: I copied over the contents from the \User location in Vista to my data partition (F:\Omea), updated the registry (HKCU\Software\JetBrains\Omea) values to F:\Omea, moved the folders in the \User location to the Recycle Bin then restarted Omea. Success!