Most people are on the 5GB plan, where anything over the 5GB's will cost you $.25 per megabyte. The new plans will cost you only $.05 per megabyte over the 5 GB limit. Your old plan will continue to reflect the higher charge unless you call them and tell them you want to change plans to the new one. Changing plans won't affect your plan dates or anything like that. All it will do is cost you 20 cents a MB less if you should happen to go over the 5GB cap.