Finally got around to seeing this. Pretty impressed with what I saw.
Despite McG being at the helm, the film is well-accomplished and works well as part of the canon series. I think that's helped by some quite obvious references to the original films - particularly T2: the bike jumping from the bridge and over the truck, the music playing on the ghetto blaster being the same that accompanied Edward Furlong's scenes, the molten metal, fights in industrial settings, etc. Then there's the blatant quotes: "come with me if you want to live"... "I'll be back". :D
They are, I think, a little self-conscious... and the unforgiving might say they were a desperate attempt to please the fans. But I think it's forgivable, if not for the aberration that was T3, then certainly to reconnect with the fanbase in the first of what is rumoured to be a trilogy.
The CGI is impressive. While I'm a fan of its subtle use, you can't make a film about killer cyborgs in the future without it. The first few scenes with the helicopter assault/escape are a wonder of technology and camera work. I had no doubt that what I was watching was CGI, but only because of the subject matter, rather than its implementation.
The cast perform well. Bale is what you'd expect and plays the role well. Worthington also does well as the mysterious co-lead. The young Reese Kyle (played by Anton Yelchin) is somewhat beige in his role, but understandable given the need to develop his character over the trilogy. The boy's going to be busy if he's to be Pavel Checkov in the new Star Trek franchise as well. Michael Ironside, despite my initial fears, manages to hold screen time without coming across like a walking cliché. Al in all, I'm looking forward to seeing what's coming next.