Hi Paul,
I wasn't thinking so much of the multi-lingual nature (although that would be important), but also things like the road signs - which vary from country to country.
I know what a green background road sign means, but does everyone else
Also I don't know what the speed camera databases are like for other countries - perhaps you're right in aiming for the UK market.
I was thinking from the perspective of adding it to my website. To make it worthwhile (for me), it would probably have to have a higher selling price with a slightly different business model (ie. free trial), and work with other countries (=bigger market). (send me an email off list if you're still interested)
Richard