I guess the vent, as it seems to be outside, is either the hatch openning for the ship or perhaps it's connected to something else such as a climate change mechanism? Alien features a few shots of small vents spouting on the surface so perhaps a connection to changed atmosphere? Or maybe I'm reaching.
Also, why are so many shots swapped in these trailers? This has the same shuttle flyby shot but swapped in orientation. Previous trailers have featured a number of swapped shots are well.
I know it's not uncommon for directors to swap shots if they feel it works when viewed against the larger assembly but I'm surprised to see it in trailers released so closely together.
Very curious as to why David / Vickers square off. Reminds me a touch - just in tone - of the two Terminators squaring off in the halllway in Terminator 2. Given the similar look they share really wondering if that scene reveals Vickers is an Android too - and more than capable of handling the strengh of another Android.
Love the sunrise shot over the Temple and look forward to hi-res version of that.