This is an action-packed, CGI-filled movie with comedy and plenty of robot fights. I had a blast and was glued to the screen from start to finish. In this day and age, that normally qualifies a movie as A material for me. I didn't check my watch once and was able to enjoy the flick without popcorn. The main actors are terrific. Several cast members from the first movie make a reappearance in this one, and the parents are just hilarious. I loved the mom and the college scene. Trust me, you'll laugh.
The plot worked and flowed well from the first movie. Sometimes sequels forget about plot and go for special effects and the return of beloved characters. But this movie made sense, in a Transformers-universe kind of way. I've heard sci-fi enthusiasts bashing the movie on a scienctific "that's not conceiveable"basis, but come on, people. This is a movie based on a popular cartoon from the 80's. Turn off the geekiness for a few hours and enjoy the bright, loud robots beating the crap out of one another to save the universe.
NOTE: I don't know that I'd take my younger kids (ages 4 and 5) to this movie because it was so violent, but then again, most of the violence was between giant robots pounding on one another. We'll see when it comes out on DVD if it's too much for them.
If you want some cinetatic fun that'll take you away for a few hours (it's a 2.5 hour movie), check out Transformers 2: Revenge of the Fallen. You won't be disappointed.