I'm having same problem. I have Vista x32 (not x64) with SP1 installed, and I have yet to see any indication that it has detected anything. I've searched the site for ideas and have run out. I ensured I was logged-in, added all conceivable music libraries (primary one is on a local networked computer), and even added the location for the Windows Media Player library file (in case that's the music library referred to). No luck yet, but anxiously awaiting any update as I was thoroughly impressed with the prior version, which I'm glad to hear can run side-by-side with this new client.
FWIW, I am running Avast Home 8.0 antivirus, have LastFM scrobbling enabled (I'm a recommendation tool freak), and for the life of me can't think of anything else tha might conflict. I'd be happy to submit any logging that may be of use... just let me know.
Best,
Nate