I also saw Transformers: Dark of the Moon. While I wasn't hyped for the movie, I did want to watch it as early as possible. I looked at my blog about the previous movie. Apparently, I liked it a lot. Hmm...I think discussing it helped me point out the flaws about the movie. At this point, Transformers has lost much of its originality. As a Bay Blockbuster, it promises action sequences and a long running time.
Plotwise, I don't think the movies was too bad. The problem is there is too many unnecessary side plots. They should have kept things simple: Autobots, Decepticon, Human involvement, and problems. However, Sam has his own personal problems that are tied in. They aren't as interesting as Transformers 1.
For the record, if you didn't like the humour in Transformers 1 than you probably won't like the humour in this movie. It's not as low brow as Transformer 2. I was suprised to see Ken Jeong in the movie. You know what to expect from him.
As for Rosie Huntington-Whiteley replacing Megan Fox, she was a decent choice, but her character is inferior.