According to the feat Melodic Casting in Complete Mage on page 44 it states:
...In addition, you can cast spells and activate magic items by command word or spell completion while using a bardic music ability. Bardic music abilities that requite concentration still take a standard action to perform.
Normal: A bard can't cast spells or activate magic items by command word or spell completion while using bardic music.
Now I don't know if there has been any statement as to which bardic music abilities require concentration and which that don't other than to infer from what is presented in the descriptive passages of bardic music abilities on page 29 of the Player's Handbook. I have read through the text and have assumed from these descriptions only the following require concentration:
Song of Freedom
Fascinate (and by extension suggestion and mass suggestion)
Is this correct, is there any official ruling on the issue?