The digital revolution continues apace.
The online revolution continues in retail.
Despite major retailers like Walmart WMT , Target TGT , and Best Buy BBY starting to offer many Cyber Monday deals on Sunday this year, the biggest online selling day of the year is already shaping up to be a blockbuster, generating record revenue.
Adobe, which tracks 80% of all online transactions at the 100 largest U.S. retailers, said on Monday that online sales had already hit $490 million in the morning, on their way to $3 billion for the day.
IBM, which also monitors e-commerce, is forecasting that online sales on Cyber Monday will rise 18% compared to last year, fueled by a boom in shopping on mobile devices. E-commerce rose 25.5% over the four-day Thanksgiving weekend, according to IBM.
If the prediction comes true, it would continue what has turned out to be a historic weekend in retail: as Fortune reported on Sunday, a National Retail Federation survey found more Americans shopped online this weekend (103 million) than in stores (102 million for the the first time, a major turning point in shopper habits.)
Of course, the online bonanza is fueled by deep discounts aimed at fending off Amazon.com AMZN , something that could ding profit margins.
“While the topline is a definite plus—consumers are also out in full-force looking for great offers. That makes Cyber Monday a meek day for margins—and that is a challenge for retailers,” said Forrester Research analyst Sucharita Mulpuru.
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