BY ANY STANDARDS, 2003 was a banner year for online retailers. At a time when the rest of the retail business was in a deep funk, holiday e-commerce sales soared to a record $18.5 billion, a 35% surge over the previous year, according to a report from Goldman Sachs, Harris Interactive, and Nielsen/NetRatings. Online shoppers spent a generous $760 on average, compared to their traditional counterparts' $490.

But don't rest on the proverbial laurels, AMR Research Inc. warns e-merchants in a recent holiday shopping survey of more than 800 Internet users. The Web shopping expansion is starting to slow. It went from a 16% increase in 2001-2002 to an 11% increase in the last holiday season. Catalog call centers are no longer a strong holiday draw, as most online shopping comes from brick-and-mortar store traffic. Seventy-three percent of consumers who bought online last year did so from the same retailers they visit in-store; in 2002, that figure was 65%.

The obvious lessons from this are that retailers must retain existing online customers and build an enjoyable multichannel experience. Of particular interest to shoppers is in-store pick-up, as 75% of respondents plan to take advantage of it in the future. And if you ever doubted that multichannel shoppers have money to spend, here's your proof: These people spent 53% more — for an average outlay of $1,100 — last year than in the previous holiday season. By contrast, the folks who went the single-channel route ponied up just $725.

Other must-haves for your operation are inventory accuracy, safety stock, and enough bandwidth. It's also a good idea to learn from the pros — or, in this case, the pro, as AMR Research asserts: “Amazon.com is the unique pure play that seems to do everything right.”