The media player 'pretends' to know what is on device, while tracker is stil indexing.

The whole tracker concept is problematic

It would be possible to modify N900 kernel to report newly created files individually, and add them to tracker database as they are created; this would solve this BRAINDAMAGED tracker design which is one of the bigger problems with N900 as-shipped.

Unless someone with real kernel chops explains to me why I'm wrong, this is the solution.