Mac: AAC (up to 320 kbit/s), MP3 (up to 320 kbit/s), MP3 Variable Bit Rate (VBR), WAV, AIFF, Audible.
Windows: AAC (up to 320 kbit/s), MP3 (up to 320 kbit/s), MP3 Variable Bit Rate (VBR), WAV, Audible.
Guess I won't be purchasing one of these, then....