CSV (comma-separated values) have up to now been a very convenient way to transfer tabulated data between spreadsheets and databases and the other way round. A promising format, already used (among others) by the framework SYMFONY 2 and by the recent Drupal 8. Instead of just allowing to represent tabular data, YAML allows to represent arrays of arrays.
Of course, xml already allows that, but not in a very human-readable way. YAML is much more readable and allows easier visual checking of the information. Do you know whether it could be of some interest to create some workspace allowing YAML dumping of arrays of arrays ?