Verizon customers with unlimited data had better start keeping an eye on their data usage. Ivan Seiderberg, the CEO of Verizon, has confirmed to the Wall Street Journal that their unlimited data plan will be replaced by a tiered plan. Seiderberg stated their prices will be different than AT&T's recently introduced plans, but who knows whether they will be higher or lower. The timeframe stated was within the next four to six months, so you've got a little time to do your homework before you have to worry about every little megabyte.