It would be useful for those people that earn money in SL to be able to set up an automatic transfer from their L$ account to their USD account. For example, if tier of $295USD is due on the 20th, setting up an automatica payment to move 80,000L from your L$ account to your USD account on the 19th, saving you having to check accounts and transfer manualy, removing the possibility of cc or failed transactions. This would be in essence the same as banks do now and would only happen obviously if there were sufficent L$ in the account.