one thing i REALLY like about the trailer is that it shys away from revealing any of the actual "details" that were all craving... rather the questions we want answered from Prometheus! the trailer just really showed the obvious: Neomorph back bursting, spore based accelerant, the crash landed ship from Prometheus, the facehugger and, last but not least, the proto-xeno.
We still get to wait for all the juicy details like... what happened to Shaw? what happened during the trip to "Paradise"? how did David get his head back on? answers to what exactly is going on in Davids lab (leaked photos)? what the 2nd Neomorph (or 3rd or 4th) will look like? How did David go about creating the Neomoprhs? how different the proto-Xenos will look (super long hand digits in trailer)? what the hell happened to all of the Engineers on the planet (again, leaked photos)? etc etc etc
Im still convined that the trailer is really only events that unfold during the first 45 minutes of the film (something tells me total run time is AT LEAST 2 hours and 15 minutes to 2 hours and 45 minutes if were lucky)