I only managed to watch it last night, and I was resisting to come in here until i watch it, knowing there's lots of moron out there can easily spoil the movie for me in here by revealing the major spoiler

for me it's not as bad as those claim to be, and of course, among all Terminator movies, T2 is still the best, followed by T1, only then TS, and I believe everyone will agreed that T3 is the worst.
TS basically is about filling the gaps of things mentioned in the past Terminator movies, eg: how JC become the true leader of the resistance, how Kyle met up with JC, and some back stories about Skynet and etc...
About the time travel thingy and when is the actual J-Day... i dun care

just borrow a famous line from Lost about time travel: Whatever Happened, Happened.
You cannot change the future or the past, whatever happened in the future, still happened, maybe under a different circumstances, under a different time, but it will still happened.
J-Day is inevitable, so does the birth of JC, death of Kyle Reese, creation of Skynet and so on.
btw, in TS, when they first show T-800, I got the urge of standing up and scream "Arnie!!!!"

but I only scream inside my heart

agreed much. gotta love that arnie scene, which made me smile and frighten at the same time
still, can't forget T3 for making the terminator looked stupid especially with that horrifying jon elton's glass