When they formed back in 2006 as a one-off group to record a song for the Snakes on a Plane soundtrack, Cobra Starship’s aspirations were slight: Former Midtown singer Gabe Saporta gathered some of his old emo pals for a lark. Now, after three albums, Cobra Starship is a full-time band, and their squiggly synth-pop sounds a lot more committed than most of the music played by Saporta’s friends these days. The group still can’t go very far without an inside joke (“Pete Wentz Is the Only Reason We’re Famous”) or a cheerleading sing-along (“Nice Guys Finish Last”). And Hot Mess’s over-glossed production is so sleek it borders on sterile. But “Good Girls Go Bad” is deservedly a hit, all hook and monster synths, plus some sticky vamping by Gossip Girl’s Leighton Meester. The band may still be looking out for the punch line, but Cobra Starship is getting seriously good at this.