T-Mobile has been pulling some cool stunts lately. Most recently, they had a group of performers take over Terminal 5 of London’s Heathrow Airport to greet tired travelers with a song and dance. It’s all part of the brand’s “Life’s for Sharing” campaign, and judging by passenger reactions — and 26 million views on its YouTube channel — T-Mobile is nailing it. Will flash mobs ever get old?

This one has gone beyond viral. The footage from the event has already been converted into a three-minute commercial and on October 29^th, two days after the spectacle, it was aired simultaneously at 10:15pm on 86 British TV channels. An estimated one in six people in the UK have seen it.

This isn’t the first time T-Mobile has assembled a flash mob (see the dance routine at Liverpool Street Station and mass sing-along in Trafalgar Square). And while this angle is clearly T-Mobile’s spin on Improv Everywhere’s Welcome Back prank, the response has been overwhelmingly positive. Just look at the smiles on those faces:

Flash mobs are great because they’re fairly cheap and can showcase a variety of talent. Plus, they produce the kind of feel-good advertising that hits consumers on an emotional level — whether they see it live or come across it later.

But is there a danger of this kind of gimmick getting played out? If more and more brands are sponsoring public performances of their own, the novelty wears off. Of course, everyone wants to create something that will go viral, but brands are quick to use and overuse an idea until consumers become jaded and it’s beaten into the ground.

Consumers are often finicky and suspicious, and when they don’t like something, they let the world know. Then, a campaign will cause the exact opposite sort of buzz than it had hoped to generate, and everyone’s left sitting around scratching their heads wondering, “Gee, why that didn’t work?” The T-Mobile performance, on the other hand, demonstrates that it’s quality of content, not necessarily the particular tactic, that leads to positive feedback and a successful campaign.

PHOTO CREDIT: Life’s for Sharing /flickr.com