DVCLiz is correct, but you can NOT bank them until your use year starts. I would probably not want to bank them that quickly though. I did that early in our ownership, and then ended up borrowing points when I needed to take a quick trip. There is really no need to bank them until just before your 100% banking window ends unless you are making a 2008 reservation that needs 2007 points added in.
For example:
You might want a 2008 Christmas ressie that uses 3 years worth of your points. You want to make that ressie in January of '08, so you would need to have your '07 points banked by then so you can use them in your '08 use year for that Dec. '08 ressie. You could also at the same time borrow from your '09 use year.