My first face-to-face encounter with the Blue Man Group came in Las Vegas, which is somehow fitting. What started as an off-Broadway bit of performance art has turned into a multinational experience, with scads of anonymous performers playing in theaters, concert halls, and cruise ships around the world. The Blue Man Group is a well-oiled entertainment machine, in which the performers are as interchangeable as the plumbing supplies used in some of their routines. That doesn't mean it can't be fun — as the touring production currently at the Orpheum Theatre proves — just that it is getting to be more than a little familiar. The production mixes in greatest hits with some new routines. The older, familiar material really feels like a hits package. It makes for an "All right! Here comes the Cap'n Crunch bit!" kind of feeling. There are some signs that the overlords — er, creators — still have an eye for innovation. Bits involving smart phones and texting evoke the childlike appeal of new objects in our silent performers. Also, videos and television appearances can't replicate the show's sheer sensory overload, such as the finale (there's an encore as well — such rock stars), in which the audience has to contend with giant beach balls, a shower of confetti and toilet paper, and a seizure-inducing light show, along with the usual Blue Man percussion-based music.