Last month, Apple gazillionaire Steve Jobs punctuated his Macworld keynote address with an audio-visual demonstration that included some major guitar riffage. The heavy-duty shredding came courtesy of Boston metal band Bang Camaro . . . which apparently never got the memo that the hair-metal era ended more than 15 years ago. Group sing-alongs, big-bottom bass, and mile-a-minute soloing are all over tunes like “Push Push (Lady Lightning)” — a tune that includes the memorable couplet, “Ooh, come on, I want to take you higher/Ooh, come on, let’s make electric fire.” Still, someone digs the band’s cowbell-propelled throwbacks — someone like video-game junkies addicted to Guitar Hero and Rock Band, both of which feature Bang Camaro cuts. “Pleasure (Pleasure)” might be a stupid — and stupidly titled — song, but it sure is a blast to air-shred to.