The directory setup is based on the instructions in the wiki:

http://wiki.dwscoalition.org/wiki/index.php/Dreamwidth_Scratch_Installation#Set_up_GitHub

Do we have something like a standard dev-env setup?  If so, we should update both this script and the wiki to reflect that.  I haven't seen how Dreamhacks get set up -- I don't have one -- but in the absence of some explicit norm, the typical Dreamhack setup sounds like a good de facto one to me =)