Can this shield play MP3 files? What about WMA, Ogg, AAC, etc?
For recording and playback of other file formats, see the VS1053 breakout board.
What sort of audio can it play?
What does it sound like?
Can this shield record audio?
Don't try this with an older Arduino (atmega168). You need the memory of an Atmega328 (such as an Arduino Uno).
What pins are used by the shield?
That means pins 6, 7, 8, 9 and the 6 analog in pins (also known as digital i/o pins 14-20) are available.