News of online PIN debit payment products popping up in the news often. ATM Direct/Acculynk and NYCE's SafeDebit are the but the latest examples. 

Persistence over the past ten years to make online PIN debit a success is admirable. In an effort to overcome prior industry missteps, Acculynk and SafeDebit are offering software-based solutions.

As noted by others (last sentence) a hardware-based module needs to be involved to secure online commerce comprehensively.  

Additionally, the usual suspects standing in the path of success include lack of ubiquity and changes to the user experience that make users uneasy.

The current interest in online debit payment options are driven by the credit squeeze being felt by consumers. If the current online PIN debit offerings can go commercial in the next 3-6 months with a broad array of merchants offering this payment option, there is a good chance of success.