A Matt & Kim concert is more than just a concert. Last night before a sold out crowd at House of Blues, the duo pulled out all the stops. We’re talking confetti and balloons, sing-a-longs and crowd-surfing. Playing on an elevated platform atop the House of Blue’s stages, singer-keyboardist Matt Johnson and drummer Kim Schifino displayed the kind of exuberance that makes you think they must be on some seriously good drugs. Not that we’re implying they’re not genuine or anything like that. Their banter didn’t at all seem scripted as they joked about everything from fanny packs to the male stripper movie Magic Mike, which Schifino said she had just watched on their day off.