Just got back from seeing this. It was pretty good, but did have some issues IMO. I'd give it a solid 7 out of 10. My main problem is that there simply is not enough Godzilla. I'm all for the "slow burn" building up to the action, but they don't give Godzilla enough screen time, even toward the end of the movie after he's been revealed. Godzilla is cool when he's on the screen though. Without giving too much away, they do leave the door open for a sequel, so hopefully that will give them a better opportunity to focus on Godzilla. Related to that, I understand the need to establish humans characters to an extent, but no one is seeing this to see Elizabeth Olsen or Aaron Taylor-Johnson (I found him especially to be pretty boring and bland...hopefully he steps it up for Age of Ultron). Some of their time on screen should have been transferred to Godzilla, especially since the military plan is kinda convoluted and not that interesting. The mistake of focusing on the humans characters caused the middle of the film to sag, in comparison to the great beginning and solid end.
So, all in all, it's a solid blockbuster that would have been greatly improved by focusing more on Godzilla, who is the real hero of the movie. I'd recommend it though. 7/10