16 hour talk time is the amount of battery life you'll have if you're on the phone for 16 hours nonstop talking.

You get 30 days of unlimited talk / text, so if you talk for more than 16 hours on the phone you'll need to recharge using the charging cord that comes with the phone.

Sorry for the confusion there.

The 16 hour talk time is in reference to the battery life of the phone, I'm guessing (the next bullet references 30 days' standby time).