It's been a busy week for Yahoo. Layoffs. A Microsoft buyout offer. And now Yahoo has announced it will drop its music service and switch over to Rhapsody's subscription service. (This makes an acquisition by Microsoft all the more interesting since Rhapsody and the Zune Marketplace would become a sibling rivalry.)

This will be a good test for the subscription value proposition. Yahoo's huge user base creates an enormous potential market. How much of that potential can be tapped is still the big question. Digital music rental simply turns off consumers. If anything is going to work, I think Universal Music Group's Total Music stands the best chance.