Well I had the UK PR1.2 running. I didn't get the update, so I flashed the N900 with the Global PR1.3 firmware.

This might be a bad idea if you have loads of apps installed and stuff, as they will be removed. This wasn't too bad for me, because the N8 is my new phone which I use on a daily basis. The N900 is just a device which I use to learn some programming on (I'm still a student)...

Either way, I don't find any major differences between PR1.2 and PR1.3 .. But, just like all of you, I would love to know the difference between the Global and UK firmware.