You see a new drop down menu option under My Account called Accounts. In Accounts, you can set up your Bank and Credit Card accounts - once again these are anonymous just like everything else on expenseRegister. You could just name your account 'My Primary Bank Account' or something like that, it is just one more way to identify how you spent your money.
There are still some kinks to be ironed out. You'll see some those and some enhancements over the next few weeks.
Thanks!