There is an unconfirmed report that Verizon may have a pretty appealing new promotion. Supposedly, they will offer a $100 dollar gift card to existing customers that sign up for a new contract and trade-in their old basic phone for a new smartphone. The promotion will go on between August 18th and September 30th. Here's a quote with a few more details that are also included in the pics.
1) Current customers with a basic phone that are eligible for a 2-year upgrade will have to purchase a new smartphone at the discounted upgrade price, re-sign a 2-year contract and add a smartphone data plan.

2) Current customers with a basic phone, but are still under a contract may be eligible for an early upgrade. If so, they purchase the new smartphone, re-sign a 2-year contract, and add a smartphone data plan.
This was leaked by a western region Verizon employee, so it isn't clear yet if it will be nationwide, but we will inform you as we find out more info.

Source: PhoneArena