It is shaping up to be a banner year in mobile sales for eBay. This week, the online marketplace’s CEO, John Donahoe, revealed that eBay will have done $5 billion in business this year via mobile phones. eBay owned PayPal isn’t far behind with $3.5 billion in mobile payments for the calendar year.

The smartphone boom and corresponding popularity of eBay’s mobile applications have made this impressive feat possible. Donahoe admits that that eBay’s applications for iOS, Android and Windows Phone have been downloaded in excess of 56 million times.

“We are seeing profound change in how consumers are behaving and will behave. We believe we are at an inflection point,” Donahoe reportedly said this week at the Open Mobile Summit. Our perspective on mobile is that it’s not incremental, it is another screen in the shopping experience. It’s a consumer that is coming back more frequently and shopping more because now it can be done at any time of the day. We know it is driving consumer engagement and customer value.”

The eBay chief added that e-commerce is a $350 billion business, representing 4% of total retail. The industry is losing its “e,” Donahoe suggested, noting that retail and e-commerce are now becoming fused together as “the line between online and offline is blurring.”

“We believe that there will be more changes on how consumer shop and pay in the next three years than there have been in the past ten or twenty years, consumers are in charge, technology enables it and eBay we are simply a technology platform that helps consumers to get what they want, when they want it, how they want it and helps merchant compete in this new commerce environment and we will never compete with them,” Donahue concluded.

Mobile commerce is big business to eBay. And the largest online marketplace in the world realizes that this cash cow can be milked even further.

As a result, on Friday, eBay unveiled its newest campaign: “When it’s on your mind, it’s on eBay.”

The advertising campaign speaks to today’s “on-demand shopper,” who prefers to shop anywhere, anytime with a mobile device, eBay says, noting that the campaign aims to prime the market for what will be eBay’s largest mobile shopping season ever as the company continues to innovate and enable consumers to shop “how they want, when they want.”

“eBay’s target customers are shopping enthusiasts — people who are passionate about shopping, whenever and wherever the moment of inspiration strikes,” says Richelle Parham, chief marketing officer for eBay. “Shopping enthusiasts are heavy online users with a particular affinity for mobile shopping, and this campaign extends eBay’s powerful brand to reach them at the moment they want to shop.”

The campaign was brought to life by independent San Francisco ad agency Venables Bell & Partners.

The effort by eBay pays special attention to prospective shoppers in categories such as fashion, motors and electronics.

Shopping enthusiasts use mobile devices to shop more than any other category of shopper. Sixty percent of fashion enthusiasts and 65 percent of electronics enthusiasts own smartphones, compared to less than 30 percent of the general public. eBay research has shown that these shoppers appreciate the excitement of the eBay marketplace and like to shop on eBay at the moment inspiration strikes.

“When the company that revolutionized how people shop asks you to do something big and new, you get excited,” says Paul Venables, executive creative director at Venables Bell & Partners. “For this campaign, we tapped into the psyche of passionate shoppers and then demonstrated why eBay is the answer.”

Using the simple call to action, “But it new. Buy it now,” the campaign reinforces the shopping experience on eBay today. Sixty-two percent of the more than 200 million live listings at any given time are fixed price and 70 percent are new products. Mobile sales on eBay are expected to exceed $4 billion by the end of 2011, and eBay’s suite of mobile applications have been downloaded nearly 50 million times, with one purchase made every second through mobile, showing a strong demand for shopping on the go.

Shopping site eBay reported that the Christmas 2009 holiday season saw a huge growth in the level of mobile commerce activity, with customers using their mobiles to buy a wide range of products, including a $75,000 1966 Chevrolet Corvette.

In the past couple of years, many people have been expecting m-commerce to develop into a significant business, based on the fact that e-commerce is now so well established and mobile will add an extra level of convenience. Recent numbers reported by eBay support that view, and show a very strong level of growth.

The key points reported by eBay include:

• Nearly 6 million people from 165 countries now have an eBay application on their mobile, and they make 750,000 unique visits per day to the eBay site.
• 1.5 million items were bought by mobile on eBay over this holiday season, triple the level of last year.
• During all of 2009, mobile sales on eBay totaled about half a billion US dollars, with a new transaction every 2 seconds.
• Luxury items were a favorite of shoppers this holiday season. Some recent mobile transactions in the US included
  • $19,108 for a 23-foot deck boat
  • $10,025 for 250 grams of pure gold bullion
  • $10,000 for a Boston grand piano made by Steinway
  • $3,888 for a Hermes Kelly bag

“Mobile is changing the way people shop this holiday season,” said Lorrie Norrington, president of eBay marketplaces. “With eBay on your iPhone, great deals are available anytime, anywhere. We see consumers taking advantage of that freedom to find great holiday gifts and deals without sitting at their computer or being stuck at the mall. eBay buyers and sellers have rapidly embraced mobile commerce this year, and this holiday season has been a mobile commerce tipping point. Shopping will never be the same again.”