I've just watched this in IMAX, and I must say, although it's not as good as the first movie, it is a lot more enjoyable than the second and third Jurassic movie.
OK, first let's get the bad out of the way. There wasn't much character developments (other than Owen and Claire, thought they get most of the screen time, other than the dinosaurs of course), and the 2 kids are not as good/fun as the original. The dialog/lines are not as good as the original as well (I miss Ian Malcolm and Alan Grant). The biggest problem I have is with the product placement. Although not on ridiculous level, there's still a lot of product placement in the first 20 minutes of the movie. Another head scratching part is on the Aviary scene. They've been in that enclosed/neglected aviary for 20 years and they manage to multiply? Like how?? The island is too small to provide food for the various dinosaurs, so how can a neglected part of the park manage to sustain such a large population?
Luckily, all those becomes irrelevant after that the dinosaurs took center stage, and oh my they are fun. The action scenes and CGI/ are very well made, and thank god for no shaky camera angle. Chris Pratt and Bryce Dallas Howard did well for the 2 main casts. And I like that they put some part of the original Jurassic Park into the movie.
So if you compare it to the fun and witty dialog, not to mention the wow factor of the first movie, then this will fall short of your expectation. But if you view it just as a summer blockbuster film with back to back action, then it will be a fun ride that won't disappoint you.