I'm more or less in the same position as Mr Woods is. There aren't many dulcimer players in Utah, and those who know each other don't colaborate much (mostly due to road distance). If you ask me what my playing style was I'd have to answer "Northern Youtube". I think a person's region probably had a lot more impact on their style before the internet was around.
That said, I'd be willing to bet that your peers have a very profound impact on your style. I fell in with a group of fiddlers (bad company, I know

), and most of the tunes I've managed to learn fit with their repertoire for the sake of being able to jam together. Utah's old time and bluegrass comunity is very heavily influenced by what goes on in the Weiser contests (just across the boarder North of us). Logically speaking, my style has to have been affected by the region I play in, although I am not musically educated enough to tell you how or by how much. And you'd probably have to extend the scope of observation beyond the dulcimer community to see it, if it can be seen at all.