The visuals in the trailer look great, awesome, grawesome. Someone before had said that the trailer is a mess because of no attempt at a narrative, but I think the trailer works great as a teaser to get people interested and asking questions. Kind of like Cloverfield, they don't explain anything but instead show you something that looks awesome and mysterious. Dr. Manhattan looks so cool and that insane contraption at the end will definitely have people wonder what Watchmen is about. I think the trailer does a good job in that respect as being a teaser.

Watchmen
Trailer
(2:20)