I saw the premier of this film. I caught the very first screening in my town, (or rather, a nearby town) and it was AWESOME.
Crank: High Voltage (or Crank 2) maintains the constant action style that Crank 1 did, with even more gratuitous sex and violence. The film brings back a lot of the still-alive characters from the first movie, and even some supposed-to-be-dead ones. You need a little belief-suspension to grasp Crank 2, as even more improbable things happen in this one than in the last one, but it doesn't really matter because the film is so exciting. And I for one cannot WAIT until the DVDs come out.
I don't want to spoil anything, but a Crank 3 is POSSIBLE.