Hi, I'm new on this site and, like Speedy Hawk, I'm from England. Yes, sign does have regional differences and, because sign was once prohibited (a meeting in Milan in 1880 or 1890), children learnt to sign in the schoolyard, hence the regional difference. So born deaf people can tell which school a person went to by the signs. For hearing people, your signs tell people which region you are from but, there again, if your teacher came from a different region to where he or she was teaching, that might confuse it a little bit.
Once you get into signing, you start to recognise the different signs for the same words e.g. I can say 'people' in BSL in about four ways, 'hospital' in two and the numbers vary from region to region too.
It's all good stuff!
Lottie.