"If you're already set on seeing Looper, I'd avoid any trailers from here on out. They don't ruin the movie, but they tip a few little things that are fun to discover in the context of the movie."
"Just to clarify - I approved all the trailers, they're great and they won't ruin anything big. But the small things they tip are fun to discover in the movie."
I find this incredibly odd, because why would you ever approve of a trailer that you don't actually want people to watch? However, I do believe trailer-mania has gotten a bit out of control with the 5-10 trailers we get for a blockbuster.
Personally, I thought this looked pretty damn awesome and reminded me of first watching the trailer for Inception. Yes, I'm sure I know more than I could have now, but I can't see anything that will ruin the experience of seeing it for the first time. I'm gonna refrain from saying much else, in case anybody does not want to watch and would just like to go see it. So...watch at your own risk, but if you are on the fence at all, do it.