There's always a lot of excited posts here on the DIS as soon as a new code comes out.
Also you can always check the discount section here on the DIS for any codes that come out - they keep a list and update all the time - here's a link:
http://www.wdwinfo.com/discounts.html
You can also check the mousesavers website and sign up for their email deals newsletter to notify you as soon as a new deal comes out.
As far as the PIN code postcard/email offers, this is what allears says about those:
For the past several years, Disney has regularly sent out masses of postcards (and more recently, e-mails) that offer deeply discounted Walt Disney World resort rates to the recipients. I can't publish those discounts, because Disney uses a PIN number system so that only the recipient can use the code. (When you call in with your PIN number, they match your name and address to it. You can't share the PIN with anyone else.)
How do you get on the lists for these special postcards and e-mails? No one knows exactly, and believe me, I've done a lot of research on it. It appears that Disney's marketing department uses a variety of lists at different times.
If you want to have the best possible chance of getting these mailings, it's definitely a good idea to register with Disney.com and be sure to click on the boxes that indicate you're interested in Walt Disney World. You might also want to go to DisneyWorld.com and request a vacation planning video. It also appears that they may use mailing lists from DisneyShopping.com, subscribers to Disney publications and Disney Rewards Visa card members. In short, sign up for anything Disney (especially Disney World related) you can, and keep your fingers crossed!
If you are a repeat resort guest and have already subscribed to a lot of Disney lists, it's possible you have received a discount e-mail but it went into your "spam" folder or was filtered out as junk mail by your e-mail provider. However, if you are in the Disney reservations system, the discount information should be associated with your name. For that reason, when you call the Disney Reservations Center to make room reservations, it's worthwhile to make a polite inquiry. You might say something like "Would you mind checking to see if I am on the list for any room discounts? I'm afraid I may have missed a promotional e-mail." Don't bother calling about this if you have never stayed on Disney property before -- you almost certainly won't be in the system.
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You mention that you usually go in January - here's what was offered last year for January, and when it was offered:
Check ins between 1/1/07-2/14/07 Annual Passholder room-only rates became available on 11/1/06, exp 2/14/07
Check ins between 1/1/07-2/14/07 Florida resident room-only rates became available on 11/2/06, exp 2/14/07
Check ins between 1/1/07-3/8/07 package discounts for Canadian residents became available on 10/16/06, exp 12/16/06
Check ins between 1/1/07-3/8/07 package discounts for Disney Rewards Visa cardholders became available on 10/31/06, exp 12/16/06
Check ins between 1/1/07-3/8/07 package discounts for general public became available on 11/2/06, exp 12/16/06
Hope this helps! Based on above, you probably should start checking here on the DIS daily for any next January deals that might come out soon!
