The iPhone – and particularly the iPhone’s Passbook feature – is quickly making the traditional business card extinct. Real estate agents, huge users of business cards, are now one of the biggest proponents of Passbook as Re/Max Regional Services adopts iPhone-based business cards for its 4,500 agents and brokers. Agents in Tennessee, Georgia, Kentucky, Southern Ohio and Southeastern Michigan will use iPhone’s equipped with a “CardSense” feature that includes a scannable QR code on the lock screen. A QR reading app then grabs a copy of the business card…

“This capability makes it a snap to share contact information at the office, trade shows, networking events, open houses or anywhere else frequent, fast access to a Mobile Business Card is needed”, developer Vizibility said (via AppleInsider).

The real estate chain becomes just the latest business to adopt Passbook, a brand new iOS 6 stock app.

Soon after the feature was introduced as part of iOS 6, airlines began using Passbook for boarding passes. In what could eliminate all of those store loyalty cards and paper coupons, retailer Target also has jumped on the Passbook train, testing the feature as part of its own app to deliver coupons, as well as announce store specials and maintain shopping lists.

Although Apple’s marketing honcho Phil Schiller has said the iPhone maker does not view Passbook as an e-commerce tool, credit card firm American Express took the first steps in that direction. In September the company introduced an app that allows Passbook users to check their car balance and view recent purchases.

With our phones quickly becoming our wallet, it is only time before the iPhone moves from serving up coupons to making cash transactions via credit and debit cards.

How long before you begin paying with your Passbook-enabled iPhone credit card?

Is security the only issue holding back that advance?