Just as importantly as those results, Wet Seal's Keim also offered some hard-earned wisdom from the past year of marketing on social networks and smartphones. Here are some lessons learned that I picked out of his discussion:

Be in the game--or else: When Wet Seal went to create its Facebook fan page, it found someone already had claimed it. Fortunately, it was one of Wet Seal's own stores, which it had done it just for that location. Keim’s warning: "The reality was, we needed to get out there. … If you don't get out there, someone will fill the gap."

It can take time to catch on: When the company has put out a new tool, whether on Facebook or the iPhone, it's rarely an overnight sensation. "It typically takes six months to get engagement of one of our initiatives," Keim said. However, you will get feedback quickly from a small group of early adopters, and need to address it. And your infrastructure needs to be ready well before any traffic spikes. Wet Seal first launched iRunway on a single server, since there wasn't a big user base. When that server went down briefly, within a day there were six complaints and the app’s ranking went from five starts to two. The app's now split across six servers.

Different platforms, different actions: Girls tend to create content--outfits--on the Web site, but they share those outfits using Facebook. iPhone users generate the most e-mail--20 times more than they generate using the Facebook app--but they don't do a lot of outfit creation or sharing by smartphone. They don’t go into the Facebook app via iPhone much. Wet Seal tried its Virtual Runway app in stores, to show the outfits girls made on kiosks, and it wasn't a big hit. On Facebook, it has been a big hit. The lesson is that social, mobile, and e-commerce strategies have to complement each other. They'll each do different things for the same customer.

Know Your Audience, Part I: To succeed in this market, Wet Seal needed its executives experimenting with social networks and smartphones. That meant doing a lot of things "IT doesn't like to do," Keim said. Like getting executives iPhones to use, and opening Wet Seal's firewalls to Facebook and Facebook-based online games, like Farmville. Getting execs to use iPhones wasn't hard, but getting them active on Facebook was tougher. The IT team urged executives' daughters to show them how they use Facebook. "While our executives don't use our clothes, their daughters do," Keim said.

Know Your Audience, Part II: When Wet Seal wanted someone to monitor its Facebook fan page, it turned to someone who was doing a lot of posting on the site--and gave her an internship.

Facebook is a customer-support gold mine: The intern isn't the only person checking the site. "For customer service, it's one of the primary tools they use to know if there are problems out there," Keim said. Don't expect active social networking types to necessarily call about a problem -- they're as likely to just post and vent with friends about it. Wet Seal doesn't erase complaints, but tries to resolve problems in that environment, so people see the issues getting taken care of.

Keep It Current: With its iRunway app, Wet Seal is updating the functionality about every three months, adding some things and dropping others that haven't caught on. When it comes to content, that has to be changing constantly to bring people back. For Wet Seal, the only viable answer for that is user generated content, like the outfits that girls create. That's cost effective, of course. But it also brings the connection and sharing girls want.

Does any of this apply to you and your business? Perhaps not as urgently as it does for Wet Seal, with its hyper-connected teen audience. Perhaps. But without a doubt, some element of it will. Just like Amazon and Google shape what people expect on every other Web site, from banks to governments to company intranets, Facebook is shaping how people expect to interact with each other. And companies such as Wet Seal are doing the tricky and sometimes humbling work of figuring out how a new generation of customers expects to use Facebook and other interactive tools to do business with you.

Recommended Reading: Global CIO: You Do Allow Work E-mail On iPhones, Right? InformationWeek 500 No. 1: Inside Vanguard's IT Innovation Strategy Slideshow: 12 CIOs' 'Career Killer' Pet Peeves Global CIO: UPS Provides Peek Into Future Of Wireless Microsoft Office 2010 Adds Features For Browsers, Smartphones Global CIO: Ford's Challenge: Social Networking At 70 MPH Global CIO: Fear Of Facebook For The Enterprise Global CIO: 5 Points To Make When Your CEO Cries Cloud Global CIO: 5 Ways Royal Caribbean's CIO Taps Emerging Tech Chris Murphy is editor of InformationWeek.

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