Crunchgear has already pointed out that these Microsoft Stores are clear knockoffs of Apple Stores, and this spontaneous dance thing is a knockoff of Improv Everywhere

But this scene is troublesome for reasons beyond that:

• It just hurt my heart to watch this. It made me feel bad in my heart! It was deeper than pity and more potent than sadness. I just kept thinking: "No, no no no." and "But why? Why, why why why?"
• I had to force myself to sit through it. It was like watching a child pick its nose, slowly and then bring it to you full of pride as if the kid had done something worthwhile. 
• How is this supposed to encourage sales? If I'm walking by this in a mall, I see a bunch of brightly colored t-shirt wearing people dancing in unison, and I'm thinking: "Oh that's nice. They've let the developmentally challenged out for a field trip."
• It's way too long. It's actually the full four minutes and 45 seconds. Who does that??
• WTF does this have to do with helping people understand Microsoft products? Will corny dancing help prevent spyware and viruses from destroying your computer?
• What's up with those people not dancing and not even paying attention to the dancing? They're just on laptops in the background like this is a normal situation. This is not normal! It demands attention! Horrific, cringe-inducing attention!
• Why do I have a feeling this is all Steve Ballmer's fault? 

I can only hope no one at Microsoft has heard of the Cupid Shuffle yet.