Ok, maybe the comparison with mp3 and ogg is not very correct, because Stems is made mostly for DJs and other professional music producers. By the way, if you make scratches using Traktor DJ app for iOS, you are a music producer too.
So, Stems audio format, unveiled by Native Instruments earlier this year, stores data in four different tracks inside one audio file. It means that you don’t need to search original recording files or tamper with different software to filter out frequencies you need (drums, vocals and others). Now all musical data in the file is already split up into tracks and ready for remixing.
Beatport, Traxsource and some other music retailers have already began to offer songs in Stems. Beatport, for example, offers its online player, where tracks of every Stems file is split up into drums, bass, synths, and vocals.
The new format is also backward compatible and can be played simply as MP4.
Surely, there are several flies in the ointment. The files have rather large size, the songs in Stems audio format are rather expensive and only Native Instruments’ Traktor range of software and hardware can work with it.
Anyway, the new format have a chance to become popular after releasing developer tools and after other companies begin to support it.