Arduino as USB Device on Mac OS X

Hi,

I've searched the docs, references, FAQs and forums but couldn't find anything on this:

? How does Arduino present itself to USB on Mac OS X? I mean, are there Vendor or Product Ids? Device class and subclass? Endpoint specs, etc.?

Other than from its own development environment itself, how does Arduino interact with the system?

Is it possible, for example, to make the Arduino advertise itself as a MIDI device to the system? I managed to convert analog input to MIDI controler data within the Arduino and to send it to the serial port, but how do I catch on the other side.

The FTDI chip basically gives you a TTL serial port and wraps it up in USB. It shows up to the Mac as a serial port. You have to use the FTDI driver and it can't show up as a MIDI device.