I think it would be interesting to be able to tag/bookmark an audio position.

Let's say you're listening to a podcast. If you wanted to take note about a statement that's made, it would be useful to label the position in the audio.

I often take note of time position in audio or film when I'm referring someone else to it in order to see or hear something in particular.

I believe this would be useful in audio for quite a few purposes: keeping track of a lecture or speech, or learning how to play a song with an instrument (you could tag the different riffs, solos, etc.)

Yes, definitely. A bookmark feature has been on our TODO for ages, and in 2.0 we already have the beginning of an implementation for this feature.