I just got a new Macbook Pro. I know it's an Intel processor, but is it 32 bits or 64 bits processor?
Enter this into Terminal:
If you see
at the end of the string returned , your OS X kernel suports 64 bit.
Also bear in mind you need to hold down the 6 and 4 keys while booting to startup with the 64 bit kernel ( there are other ways to accomplish this as well )
At least this was the case on recent Macs - I assume the new MacBook Pros released in April 2010 still boot by default into 32 bit mode as well.