I'm guessing as far as how the tickets will work, it will be quite simple:
You buy the passes (any amount of days) based on the level of Value, Regular and Peak. If you buy a 5-day Value pass, you can go during the Value days only. If you purchase a Regular pass, you can go on regular and value days, or buy a 5-day Peak pass (which would allow you to go whenever you want) etc...
This would really benefit Disney since there are a very limited amount of Value days. The longest stretch in a row is 5 days (all mid-week), so, most people are going to be forced to pay for a Regular priced pass. (Ex if you go Sept 8-15, you would have to have a regular pass to cover the 8, 9, 14, 15th). But, they can still come across as "looking out" for the budget-conscious traveler, since they do offer select weeks with 4 or 5 days in a row of Value days.