I use Notational Velocity, not nvALT, but I *assume* my Hazel rule + Automator workflow would work for it, as well... Check out
http://www.noodlesoft.com/forums/viewtopic.php?f=3&t=2189. It'll take all your notes and archive them into the specified folder/group of a specified DEVONthink Pro Office database, bypassing the Global Inbox and the need for sorting through all the notes later by hand.
I haven't found information on if the Automator actions are available for all varieties of DEVONthink, or just for DEVONthink Pro Office, but I'm making a second assumption that they are.