You're welcome.

Now that I've had my replacement N900 for several hours, I've had a chance to play with it some more. I know that this is going to sound odd and I have no hard evidence to back it up, but...the replacement seems to work a whole lot better than my original one in several respects, not just in the lack of reboots, for example:

The audio quality on voice calls seems better. Less muffled somehow and with enough extra 'top' to help hear the caller when you're in a noisy environment.

The GPS is quicker to get a lock and there seems to be less of a tendency for your position to 'wander' on the map.

The battery doesn't seem to be getting used up at such a fearsome rate.

The camera doesn't suffer from annoying reflections of the flash coming of the chrome-style plastic surround.

As I say, I've no real evidence to back these claims up, but I'm a lot happier with this new one than with the original.

Edit: Not strictly true...see this thread:

http://talk.maemo.org/showthread.php?t=36675

For some pictures I took with the old and the new, showing the flash problem.