In a Wall Street Journal report published early this morning, Verizon COO Lowell McAdam confirmed that when the iPhone 4 launches on Verizon’s network early next month, customers will be offered the same $30 data plan they offer for other smartphones.

Though AT&T stopped offering unlimited data plans last summer ahead of the iPhone 4 launch, the carrier allowed existing customers already using the unlimited $30 per month data plan to keep using it. Many of those current AT&T customers may decide they have no reason to stick with AT&T anymore if Verizon will offer them the same unlimited data plan for the same price as a new customer.

The CDMA iPhone 4 is expected to launch on Verizon’s network February 10th, with preorders for existing Verizon customers to begin February 3rd.