TD Bank Financial Group, the Toronto-based parent of TD Banknorth, today agreed to buy New Jersey-based Commerce Bancorp for $8.5 billion in cash and stock. Commerce Bank will be rolled into the TD Banknorth brand. That will give TD Bank Financial Group more than 2,000 branches in North America and approximately one-quarter of a trillion dollars in deposits. TD Bank Financial Group will become the seventh largest bank in North America as measured by branch locations.