In case you missed it...
Just tried this again after a break. Download OTA at http://google.co.uk/glm
I think you'll need the BIS browser (or unblocked Blackberry Browser/BES service) to do it. Also set up your general APN connections properly to make it work.
Anyway, I got v1.2.3, and although it implies it still only supports US and Canada, I can now see the UK too. Maps, satellite pictures, directions, etc. Very cool.