Saw it yesterday. I give it a solid 8/10. Fast pacing (maybe too fast), Asgard looks fantastic, and everyone has great chemistry with each other. Loki is exactly how I envisioned him to be.
Thor is very charismatic and gentlemanly, I love this interpretation instead of the usual 'arrogant god' portrayal.
But props must be given to Stellan Skarsgård. His role is a minor one but the subtle things he does even when the camera isn't focus on him really adds a lot of layers to the character.
Be sure to stay for the after credit scene. Ranks as one of the best so far from Marvel movies.