I am with you on this, when I first watched the films Richard Harris was so similar to how I had imagined that when the Michael Gambon came on in the third it jarred too much for me.
For me the first two films are still the best after these they have gotten steadily worse for me personally.
I'm not all that keen on 3D, especially considering I have to wear glasses at the cinema already so I look a right plonk with the 3D ones over the top. Also it's cheaper to watch in 2D, defintely going on opening night, as long as it's a friday
Its a trailer that is representing the film as a whole which I thought was pretty clear having read the text that is shown during it which goes on to say its being split into 2 parts.
But to those who don't read the books, they'd know he was working for Voldemolt purely from his first scene in HBP. (When Bellatrix & Narcissa go to his house to get him to protect Draco)...
yeah that makes sense. then they'll release the 7 films altogether for maximum profit. Probably along with a special collector's edition at twice the price.