i hope there is a 4th, and i hope cameron comes back to do the writing/directing. not saying mostow did a terrible job, because i like the direction he took with the series, but just the fact that this project was part-brain childed by cameron and also t3 had some continuity errors that kinda irked me a bit. its what ive been waiting for all along though, the actual war between the machines and the humans. and yes, i dont see a need for arnie in this one. perhaps a cameo would be nice, but yeah, the movie doesnt necessarily have to revolve around him.