There’s so much going on in this trailer. We can see that there likely will be no real use of Donald Blake, since when he lands he recognizes that he isn’t on Asgard anymore and they probably thought the whole transformation thing would be too convoluted. The lack of Donald Blake might make for an interesting romance dynamic as well, as we can clearly see Sif in the trailer so Thor has an Asgardian honey and a love interest in Jane Foster as played by Natalie Portman. The banishment of Thor by Odin seems to stem from Thor starting a war with the frost giants. This probably happens as a result of Loki tricking him or something.