I spotted in this forum thread that id software's Christian Antkow posted remarks on a shacknews message board including, "Heh, actually, Nerve finished a bunch of maps, but some of them didn't make it into the retail release. Plans are currently to release those maps at some point in the not-so-distant-future". The forum thread also goes as far to point out one of the maps is titled "Trench Toast". Mmmm, I can almost smell it now...