According to the recommendations at http://www.w3.org/Addressing/URL/4_URI_Recommentations.html:
Reserved characters Hierarchical forms The slash ("/", ASCII 2F hex) character is reserved for the delimiting of substrings whose relationship is hierarchical. [...] Note The similarity to unix and other disk operating system filename conventions should be taken as purely coincidental, and should not be taken to indicate that URIs should be interpreted as file names.This scheme is set forth normatively in RFC 3986.
So, if you want the hierarchical scheme for your URIs to match that of your file system, you should use the forward slash - but not because it's the UNIX way of doing things.
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