Continuity mistake: When the aether enters Jane, just before she ends up back on earth, she is cross-like in a sea of red, but she is wearing a breastplate. She does not get given this until she is taken to Asgard 15 minutes later.
Continuity mistake: Sif has a wound on the left side of her forehead which disappears when she arrives at Asgard.
Continuity mistake: Thor has a massive boulder thrown at him. He ends up with a cut on his right forehead that moves to his left in another scene and back to his right in the next. Along with inconsistencies to the scar and placement at the end when he's holding Loki. (01:18:50 - 01:20:20)
Continuity mistake: After the battle of Vanaheim has ended, the scene cuts to Asgard where Odin watches people practicing battling and is joined by Thor. The shot after Odin says "Vanaheim secure?" shows Thor with his head half turned to Odin. Next shot he's suddenly looking at the battling people without his head turned an inch. (00:10:15)