Ooh, those microtransactions are tricky things. All too often, business models built around them feel nagging and unpleasant, restricting rather than offering opportunities. One use of them which does sound reasonable, though, is the Karaoke app for Xbox 360, coming later this year. It'll operate on the same model as actual karaoke booths, charging for the time spent singing rather than per song.

Run with online karaoke service The Karaoke Channel, the app named simply Karaoke will let you sing along to over streaming 8,000 songs while your avatar boogies along. You know, karaoke. You can sing anything in the library but must pay for your time. 2, 4, 6 and 24-hour time blocks will be sold for Microsoft Points, at prices yet unrevealed. If the rates are reasonable, it could work out better than permanently buying individual songs in the likes of SingStar.

The announcement explains that Karaoke will have game-y trappings like money, props, and other doodads. Because video games.

The Karaoke app should launch "in time for the holidays." If you're curious what exactly is in the music library, check it out with The Karaoke Channel's browser version.