I seem to remember a discussion about this a year ago. If I remember correctly the RTV script can only handle a list of a certain length, whereas the admin scripts can handle a nearly indefinite length?
Even if we only have a short list, most of the maps James has listed as recommended would be worthwhile to have on the list.
I think Zero's intentions with the rating system was to create an automated system that would put maps we all liked into the RTV list (like a Top10 or 20 list). It's a great idea but takes work and Zero has a lot on his plate.