Now that MP3Tag supports WAV/RIFF, I would like to request that CART chunk capability be added in addition to INFO.
Cart is a tagging format used heavily in broadcast. It would be helpful in many broadcast facilities to have a tagger that could read/write these chunks.
Here you can find some PowerShell code to read (a part of) the cart chunk data. Here you can find a free available data definition for the cart chunk data part.