The second Hulk film was a million times better than the Ang Lee production- it felt much more like a marvel venture, whereas Lees seemed like Hulk was a vertigo title. I state that as context for what I am about to say about Thor.
Saw it last night. The only real complaint I would have against it is the pacing- the film runs for around 2 entire minutes "in the present" before turning into a (roughly) 25 minute long flashback, starting with Thor and Loki as children then going through everything that lead up to the opening scene of Thor smacking into the desert. The rest of it kind of suffers from the fact that it is basically part one of a two-part deal, with Avengers being the next thing to happen in the continuity. The last act of the film just doesn't feel like the end of anything, which is pretty much a necessary evil with this kind of mega-project.
The film looks really good overall, the humour is well executed and by no means overdone, and Natalie Portman is actually cast fairly well as a goofy person.
The Stan Lee cameo is hilarious.
I will put spoiler tags on this bit just so, even tho it was mentioned earlier Hawkeye is totally in the film- I have read in some places that his appearance seemed "forced" or whatever but I didn't really get that from it- Thor is trashing the site of a SHIELD investigation in pursuit of his hammer and the site director calls for "somebody up high", so a dude who is not in costume stands in front of a weapons rack and almost reaches for a rifle before settling on some kind of wacky composite bow- he has maybe 3 lines, none of which is anything more than him communicating the status of the target, and only once he is referred to as "Barton"- no costume, no nothing, and the pursuit of Thor is concluded without Hawkeye even so much as nocking an arrow IIRC
I think the best aspect of the film, for me, was just how Marvel it was overall- you get Marvel Deaths, very mild violence (yet still blazing action) and if you have read enough silver age Marvel featuring Thor, no surprises- every time something you KNEW was coming happened it delighted me (such as for instance the obligatory Odinsleep)
Overall it is better than a lot of ways I could imagine Thor being handled- if you want something deep (like an Ang Lee film) you are NOT going to get it- if anything it was almost like a cheesy 80's film with much better writing and awesome effects- but I do believe it was a worthy big-screen introduction to the Odinson