Merchants score Senate win in fight over card fees

The amendment that cleared the Senate involves interchange fees on debit cards, but not credit cards. Debit cards are being used more as customers have become less willing to borrow during the recession. Still, swipe fees from credit card transactions make up a bigger portion of bank profits than fees from debit transactions.

via The Associated Press: Merchants score Senate win in fight over card fees.

If this becomes law, can pure online merchants that use payment gateways like AuthorizeNet, Payflow Pro, or even Paypal, categorize a transaction as debit and benefit with the lower processing rate. Since no one enters a PIN during a transaction, is this possible with an online shopping cart?