Opening session speaker Kausik Rajgopal, director at corporate management consulting firm McKinsey & Co., took a poll of the packed room using the Money2020 app. Attendees used their phones to vote from their seats.

The results revealed that attendees think traditional financial institutions, a category that included credit unions and banks, are most likely to lose in the current payments flux.

Who will win? "Non-traditional financial institutions" won the most votes. That category includes PayPal but also, possibly, Apple, Amazon, and many other non-banks.

In a breakout session, three of four panelists loudly agreed that branch banking is dead.

Alpesh Chokshi, who runs the Bluebird prepaid card for American Express, said a key factor is that "the traditional bank has a cost structure two and one-half times higher than what we have with the mobile channel."

When using the mobile payments channel, the consumer, at his or her own expense, provides the branch, he said.

And, many consumers have astonishing intimacy with their phones. Green Dot CEO Steve Streit, also on the panel, said research shows the average person touches his or her smartphone more than 200 times a day. Prepaid card company Green Dot's holdings include GoBank, a primarily mobile bank.

A more optimistic perspective came from speaker Ed McLaughlin, chief emerging payments officer at Mastercard.

"This is not a zero sum game," he said in his keynote session. "It's a tremendous opportunity to create new value in payments."

Two big companies made big announcements at the event.

Amazon took aim at PayPal's jugular by announcing its new Login and Pay with Amazon service. This payments option button will soon show up on many online retail sites, the company said.

For its part, PayPal announced a new payment service that delivers a QR code to a consumer's smartphone for use as payment from his or her PayPal account at participating retailers.

McLaughlin's point: globally, some 85 percent of retail transactions are in cash or check. Even in the US, he said, 50 percent are cash or check. "There is great opportunity in electronic payments."

Google Wallet, a huge force in the 2012 Money2020, returned in a more low key way and with a new leader, Google Payments Vice President Ariel Bardin. Last year's Google Wallet head, Osama Bedier, left the company in May.

Despite the changing cast of characters, Bardin stressed Google's dedication to its Wallet product is a long-term bet.

Bedier's speech last year was focused on Google Wallet at point of sale retail. However, Bardin focused more on Google Wallet as a tool for buying online, and described a new service that sounded much like PayPal.

Bardin also noted a new Gmail feature that allows Google Wallet to function as a person-to-person payment tool. His only mention of retail point of sale was that "Google wants to put Google Wallet in the real world, with and without NFC," referring near field communications tap and pay technology that had been central to Google Wallet's retail presence.

A general session featured a panel filled with big retailers who have signed on to participate in the merchant driven MCX initiative. Panelists, led by WalMart executive Jamie Henry, made clear that they intended to throw their collective weight behind MCX, a merchant-owned mobile payments platform where, said one panelist, demand deposit account transfers would have a place. Mainstream credit card payments were not mentioned.

Henry, Wal-Mart's senior director of payments services, stressed that "MCX has been mischaracterized as just focused on the cost of payments. Our focus in fact is on bringing forth a new, more balanced payments system."

Henry added, "I don't think consumers are sitting around waiting to make mobile payments."