Bardic music
When considering what level of action bardic music is, it's most important to consider two sentences in PHB.
1. While singing, the bard can FIGHT but cannot cas tspells, activate magic items by spell completion (such as scrolls), or activate magic items by magic word (such as wands).
2. As with inspire courage, a bard may sing, play, or recite a countersong while taking other mundane actions, but not magical actions.
I would personally translate the FIGHT action to mean attack and defend. As one can only attack with a standard or a full action, the use of inspire courage or similar abilities cannot be a standard action...it must be a move-equivalent or free action. Please note that speaking is a free action. Secondly, specific rules here were meant to bar the use of magic in conjunction with bardic music and nothing more, as evidenced by the second sentence cited. I hope that helps to clear up the matter.
Personally, I believe that bardic music should require concentration and be a free action that prevents the use of other magic due to its need for concentration.