I have recently switched from a Windows Machine to a Mac Running Osx and I'm having difficulty finding the serial port baud rate settings in the osx preferences.
In windows it was controlled under device manager, does anyone know where it is in Osx?
It depends on the application accessing the serial port, what are you trying to do?
Thanks for the reply, I'm trying to upload code from the mac to the arduino.
Say I set the baud rate to Serial.begin(57600); in my arduino code, On my Windows machine I needed to change the serial setting in the device manager to 57600 for uploads to work.
I guess I'm wondering if I need to do the same in Osx, and if I do, how.
But what program are you using to send data to the arduino... 
That's what matters. You can use 'screen' from the terminal.
screen /dev/tty.usb(someotherstuff) 57600
Ill be using max/msp for the most part,
Thanks for the 'screen' suggestion, I will check it out.
Ill be using max/msp for the most part,
max/msp should be setting the baud rate, then. As a previous post stated, the application should set the baud rate.
The bootloader speed is hard coded to (I think) 19.2k baud. You really accomplish nothing related to the bootloader by changing the baud rate in windows or the serial.begin() call - the bootloader has its speed, and the avrdude command line issued by the Arduino IDE sets the baud rate on the computer end to match. Your application will need to do the same thing.
-j
Sweet, Thanks for clearing that up for me.