Just to clarify the 180 + 10....it can be a little confusing.
If you are staying OFF SITE (i.e. NOT at a Disney owned hotel), then 180 days before you want a reservation, you can call or go online and make your reservation. For example...today is July 21....if you want a reservation for January 17, 2014, today is your 180 day mark (go
here to plug in your date and know when 180 day mark). Tomorrow, you can come back and make a reservation for January 18....and so on.
If you are staying ON site at a Disney hotel, then just like those staying off site, today, July 21 you can make a reservation for January 17......HOWEVER, the "+10" advantage for those staying on site, is that you can ALSO make a reservation for January 18, 19, 20, 21, 22, 23, 24, 25, and 26. That's the +10.
So you still can't start until your 180 day mark....but you can make 10 days worth of reservations all at once, so in essence you get in before those staying off site, because they have to wait and come back tomorrow and the next day and next day, etc.
I only post this because I see a lot of people saying it's 190 days, but that's not quite right. Hope this helps clarify it for those that are confused.
Oh...and to answer someone else's question.....it doesn't matter if you're on the dining plan or not.....it's based on whether you are staying at a Disney owned hotel or not.