Once an event was deemed a success if industryites showed up, networked and went home with a gift bag with a sponsor’s products. Those days are over. Now events must have a digital and interactive element that goes viral, and guests are expected to not only interact with sponsors’ products but to also get online and post to Facebook about the event.

Those pop-up photo booths at parties may be amusing for guests, but look closer, there’s a secondary purpose. Images come with a sponsor’s logo and often link to a Facebook page or website. On a bigger scale: the June “Transformers: Dark of the Moon” premiere takeover of Times Square yielded dozens of pages of YouTube videos.

“Your event can no longer be localized, it has to be viral on some level,” says Mia Choi, founder of Gotham’s MAS Event and Design, an event planning firm. Events are now about creating online content.

Content can encompass immediate social net posts via Twitter and Facebook, an online link-up or webcast or digital media within the event itself, such as a silent auction via an iPad app.

Sponsorships have always been the best way to augment event budgets in the era of austerity, but now sponsors want more bang for their buck. Event planners have found that the lately best way to maintain sponsor relationships is to integrate the sponsor into the event creatively and propel their brand online.

“The idea is to be subtle but also to get the message across,” says Chad Hudson, prexy of Chad Hudson Events. (His firm produced the “Transformers 3” Gotham premiere party and co-produced FOX’s “Glee 3D’s” Westwood bow.) Partnering with sponsors that make sense for a film’s theme – like Warner Bros installing a Godiva chocolate lounge for the “Valentine’s Day” premiere, for instance — is the best practice.

“How a brand leverages that sponsorship is really key on how effective it will be for that brand,” says Chris Ryan, VP of L.A.-based R3 Marketing. At events, brands now ask for “build out” — a branded VIP lounge at a post-premiere party is one model — and a share in social media.

Sponsors also need to give partygoers a reason to tweet. To that end, event planners must create immersive experiences, which can range from a photo backdrop that encourages guests to instantly share with cellphone cameras, to a party vignette (the chocolate room) that confers a story, to building an installation that instantly creates massive online awareness and interest (think Target’s multi-media fashion spectacular and transformation of the Standard New York in August 2010).

As Ryan describes it, this is new-generation sponsorship — brands are not just sponsoring events, but reaching the audience there and making a meaningful connection. More than just logo plastering (though this tradition is healthier than ever), “brands need to recognize, if you spend money on a sponsorship, you also have to spend money to activate it,” adds Ryan.

A contest on Facebook or Twitter related to an event is one way to maximize sponsorship efforts. Virgin America did just that with its “Real Steel” tie-in with DreamWorks Pictures. Not only did the airline plaster a “Real Steel” robot image on a plane (unveiled by star Hugh Jackman) but also sponsored an online contest for fans to attend the pic’s premiere.

“It makes our job as event people on some level more difficult but also more interesting,” Choi says. “We’re no longer just party planners, we’re marketers.”

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