I'm sure most of us who have been in bands have had bright ideas for the perfect band name, only to google and find of course it's already being used. In fact it can seem like all the good ones are already taken. I think it's pretty obvious that if some-one local has a similar name you don't use it, especially if they are in a similar genre. The further away they are geographically, musically, and in their market/audience, the looser I think we can be about it. So if a part time blues musician with a very local audience in one part of, let's say, the Netherlands wants to use a name like one used by, let's say, a semi-pro looking bluegrass band in Montana, what do you think? I suppose it comes down to how likely it is it to interfere with the other band and their audience. We didn't have this problem before the internet.