Another mobile music marketplace just opened up to Windows Mobile and BlackBerry users called Didiom, offering wireless access to your home iTunes collection. What sets Didiom apart from other mobile music retailers is that users bid on the tracks they want to buy. During the beta period, they’re even providing a 35% bonus on sales towards Didiom credit. Eeeeenteresting. It’s all legal, but as with most digitally licensed music, it’s available only in the U.S. You can also get dual downloads – one version for your phone, and and a higher-quality version for your PC. Interested? Check out the demo for the full tour.