I don't like the trailer. It doesn't sell you on why you should care about the team (or the individuals) or what the plot is. Right now it looks like a flat out comedy and that's not going to do them any favors in the long run either. Marvel has a big issue with embracing the inherent silliness of comic book material and always goes for this corny tongue-in-cheek *wink wink* shyt. They need to start taking these properties serious instead of p*ssying out on some "Oh, we know it's silly too, you guys" because they're scared of alienating mainstream audiences.
Star Wars took its ludicrous world and ridiculous characters serious and you know why that worked? Because they sold it like a motherfukker, got you invested in bleeping droids and shyt. Marvel's not trying to sell it, they're desperately trying to convince you it's not a bad sell.