OpenMoko released the binary for the in-built GPS chip. I did some testing today and was impressed with the sensitivity of the receiver. I was able to maintain a fix with the receiver in my pocket in central London. I also left the receiver running as I took a train home and it eventually picked up a signal. I plotted the logs using http://www.gpsvisualizer.com to see where I had been!
Looking forward to intergrating the new functionality with thumbtribes.