Since I'm fooling around with USB GPS stuff today, also figured I'd stick the Holux in my MacBook (which I'm really loving). Found the gpsdX FAQ was a good starting point. Downloaded and installed the Prolific driver from the link in the FAQ, rebooted, and now see a /dev/tty.usbserial appeared.

Once the machine was back up, installed gpsdX which installed like most other Mac programs, ran the gpsdXConfig app to select the tty.usbserial device, and that was about it. Am now able to telnet localhost 2947 and type some simple commands like d to get the date from the GPS. KisMAC seems to work fine with it, and the gps2geX app fired up Google Earth, zoomed down and put an icon right on the roof of my house - pretty slick.