When you try to add Ogg to iTunes, iTunes even not allow to add Ogg, let alone to play Ogg in iTunes. Though iTunes 10 can currently read, write and convert between MP3, AIFF, WAV, MPEG-4, AAC (.m4a) and Apple Lossless, there is limited to play Ogg files. How to Convert OGG to Add OGG to iTunes on Mac Lion, Mountain Lion Overview
