I know what you mean about the GCH prices. My friend went to WDW for a full week - 6 nights & seven days - with her husband and son, during the peak holiday season of December 2007, and stayed at the Port Orleans (I think), and it was cheaper than 3 nights for 2 people at the GCH!!
Okay, about your AP question. You can always - 365 days a year - get 10% off any room at any of the DLR hotels with your AP. That's not much, but it's better than nothing. Of course, the Deluxe and Premium AP's can also get your discounts on food around DLR as well as merchandise (Deluxe is 10% and Premium is 15%). The real hotel 'bargains,' if there is such a thing, come with the special AP rates which are released every so often. These are the rates that are usually called AP7, AP8, etc. I guess the next ones should be AP9. In any case, those are the ones that really save you quite a bit of money. I switched my December 2008 plan to stay at the GCH the weekend right after Christmas to a new plan to stay at the PPH the weekend right before Christmas using the AP7 rate or whatever it was at that time (maybe APp8?), and saved about $700 from what I would have spent if I had kept my original GCH plan intact without the AP rate. So, that said, the special AP rates come along every so often, and there will be AP rates announced for the GCH sooner or later - yes, for early November, more than likely. Some of the GCH AP rates for November have been great in the past! You just have to keep an eye on the DIS and eventually people will announce it or post the rates that are shown on the special AP section of the DLR website. Then you need to make your reservation pronto so you don't lose the rate. You can reserve the room at the AP rate when it comes out, then when you get to DLR, you can get your AP and go back to the hotel to check in and show them the AP to seal in the rate.
But remember, you can still always get 10% off the hotel during the non-AP rate times of year, and DLR does, indeed, issue special PIN codes or offers on their website every so often (some PINS have already been issued this year), so you just have to keep your eyes peeled!!