fwiw - over on the xda i9000 general forum, one poster apparently purchased 3 versions of the phone, and is reporting his UK version, as well as another, both had GPS issues, but the chinese version he purchased, with firmware ending "7" works perfectly, and he then installed that firmware on the other two phones and their gps issues vaporized
if that is accurate, then it would appear to be firmware and not hardware
i've got my fingers crossed as i'd really like this phone
Take these results with a pinch of salt.
I've been doing a bit of testing, and I do have rigorous standards, so I don't just tell anything.
Here's my review:
XXJF3 firmware - Seems good initially, but then seems to falter over time. Perhaps the good reports are people just not using it properly. I use GPS Test, GPS Status, MyTracks, Google Maps Cardio Trainer. This IMHO is the best of the bunch. When it's working. When it loses Satellite signal, it will flip to A-GPS and not be very intelligent. You'll see loads of zig zag lines over the map in MyTracks as it tries to establish a lock.
XWJG5- Seems better, lines are more rounded, no big zig zag jumps. My suspicion, is that there is some clever buffering going on, but badly implemented. If you lose signal lock, the phone will go back to A-GPS and put you 100 metres away, but then it will remember your last known good and where it thinks you should be, and plot a path, irrespective of your actual new position.
XWJM2 - Getting there. Seems to also buffer information but seems to use both last known good position, heading and speed to try and constantly plot a path. Unfortunately, due to the underlying problems, if you suddenly turn right with no warning and the system loses lock, this firmware will plot you as if you're going straight on. Eventually it will figure out where you are and draw a path back. This can yield odd results, including overshooting roads, sweeping corners, cut corners, track backs...
I'd rather have a GPS that was 50% accurate and then cut me off as in the XXJF3 rather than a GPS that was 50% accurate then make up the rest as in XWJM2.
My humble opinion? Samsung seem to be doing a lot to manipulate the information coming out of the GPS, rather than fixing the GPS itself.
The Galaxy S GPS Receiver in its current state, seems to suffer from not locking onto more than eight satellites despite being able to see more, and it will not lock onto anything with an SnR < 20.
The system should be able to keep a few satellites in reserve for those times you do walk past a tall building.
Cya
Simon