Ah now i get what he wants. He only wants the polys facing him and only the ones which are not occluded. Illusion Catalyst got that as far as i remember... Edit: There is a script on SyncViews side which does that.
Not sure if its what you need since you say you want to have a marquee selection. Script just selects all faces visible according to your view. http://dl.dropbox.com/u/5274623/visibleFaces.ms Eh rereading what you said and this is probably not what you were looking for XD