Sure, the effects are amazing, but that's where all the budget went. The script is lame, and the story is so simple there's really no need for this film to be over 2 hours long. We saw it at the IMAX, but the seats were off to one side and fairly near the front, which just meant it was impossible to track everything that was going on on-screen. There's a couple of stupid new Transformers, the "Twins", who just help to dumb this moving down to the 10-16 year old category. I liked the first movie as it was a good mix of humor and effects, but this second one has gone way over the top with frat-boy humor and excessive effects.
The trailer probably does this movie a little more justice than it deserves (but maybe that's the point of a trailer!), but overall this is an enjoyable movie. Some of the action scenes are a little OTT, and at one point the heavy background music is a little too invasive in what is, generally speaking, an action movie centred around one strong character. I don't remember the last Liam Neeson film I've seen, and he's an unlikely choice for this role, but he does a great job at it. If you're looking for an action movie that's a little above the usual 'block-buster' type movie, but still doesn't require too much thought, then this is the one for you.
If you're looking for a movie that will make you think, or challenge your belief system, then this is not for you. If however you're looking for something fun, gratuitous in terms of 3D effects and gore then this fits the bill. Sure, some of the acting is quite wooden, and there's a few holes in the plot, but overall this is well worth the money to see it in a movie theater in all of it's 3D glory!