Saw it, didn't like it so much. The 'acid trip' bit was pretty mindblowing on the 3D cinema screen (plus I was stoned, natch). I dunno, I thought a lot of the jokes fell flat, i was quite disappointed.
Their formula is wearing a bit thin at this point, unfortunately, particularly the origin stories. (Dr Strange was essentially Iron Man.)
Saying that, I think the dialogue, performances and action are often so good that the formulaic nature of the 'MCU' can be excused.